Change kB to KiB

Change the style of the units to KiB, according to
https://docs.mbed.com/docs/writing-and-publishing-guides/en/latest/units/
diff --git a/yotta/data/example-benchmark/README.md b/yotta/data/example-benchmark/README.md
index 92d9012..3b66916 100644
--- a/yotta/data/example-benchmark/README.md
+++ b/yotta/data/example-benchmark/README.md
@@ -56,24 +56,24 @@
     {{start}}
 
 
-      SHA-1                    :       3644 kB/s,         32 cycles/byte
-      SHA-256                  :       1957 kB/s,         59 cycles/byte
-      SHA-512                  :        587 kB/s,        200 cycles/byte
-      AES-CBC-128              :       1359 kB/s,         86 cycles/byte
-      AES-CBC-192              :       1183 kB/s,         99 cycles/byte
-      AES-CBC-256              :       1048 kB/s,        111 cycles/byte
-      AES-GCM-128              :        421 kB/s,        279 cycles/byte
-      AES-GCM-192              :        403 kB/s,        292 cycles/byte
-      AES-GCM-256              :        385 kB/s,        305 cycles/byte
-      AES-CCM-128              :        542 kB/s,        216 cycles/byte
-      AES-CCM-192              :        484 kB/s,        242 cycles/byte
-      AES-CCM-256              :        437 kB/s,        268 cycles/byte
-      CTR_DRBG (NOPR)          :       1002 kB/s,        117 cycles/byte
-      CTR_DRBG (PR)            :        705 kB/s,        166 cycles/byte
-      HMAC_DRBG SHA-1 (NOPR)   :        228 kB/s,        517 cycles/byte
-      HMAC_DRBG SHA-1 (PR)     :        210 kB/s,        561 cycles/byte
-      HMAC_DRBG SHA-256 (NOPR) :        212 kB/s,        557 cycles/byte
-      HMAC_DRBG SHA-256 (PR)   :        185 kB/s,        637 cycles/byte
+      SHA-1                    :       3644 KiB/s,         32 cycles/byte
+      SHA-256                  :       1957 KiB/s,         59 cycles/byte
+      SHA-512                  :        587 KiB/s,        200 cycles/byte
+      AES-CBC-128              :       1359 KiB/s,         86 cycles/byte
+      AES-CBC-192              :       1183 KiB/s,         99 cycles/byte
+      AES-CBC-256              :       1048 KiB/s,        111 cycles/byte
+      AES-GCM-128              :        421 KiB/s,        279 cycles/byte
+      AES-GCM-192              :        403 KiB/s,        292 cycles/byte
+      AES-GCM-256              :        385 KiB/s,        305 cycles/byte
+      AES-CCM-128              :        542 KiB/s,        216 cycles/byte
+      AES-CCM-192              :        484 KiB/s,        242 cycles/byte
+      AES-CCM-256              :        437 KiB/s,        268 cycles/byte
+      CTR_DRBG (NOPR)          :       1002 KiB/s,        117 cycles/byte
+      CTR_DRBG (PR)            :        705 KiB/s,        166 cycles/byte
+      HMAC_DRBG SHA-1 (NOPR)   :        228 KiB/s,        517 cycles/byte
+      HMAC_DRBG SHA-1 (PR)     :        210 KiB/s,        561 cycles/byte
+      HMAC_DRBG SHA-256 (NOPR) :        212 KiB/s,        557 cycles/byte
+      HMAC_DRBG SHA-256 (PR)   :        185 KiB/s,        637 cycles/byte
       RSA-2048                 :      41 ms/ public
       RSA-2048                 :    1349 ms/private
       RSA-4096                 :     134 ms/ public
diff --git a/yotta/data/example-benchmark/main.cpp b/yotta/data/example-benchmark/main.cpp
index 44e66d9..d13cde5 100644
--- a/yotta/data/example-benchmark/main.cpp
+++ b/yotta/data/example-benchmark/main.cpp
@@ -229,7 +229,7 @@
         CODE;                                                           \
     }                                                                   \
                                                                         \
-    mbedtls_printf( "%9lu kB/s,  %9lu cycles/byte\r\n",                  \
+    mbedtls_printf( "%9lu KiB/s,  %9lu cycles/byte\r\n",                  \
                      i * BUFSIZE / 1024,                                \
                      ( mbedtls_timing_hardclock() - tsc ) / ( j * BUFSIZE ) );         \
 } while( 0 )