Consistently use the name tinycrypt over uecc

We called in tinycrypt in the file names, but uecc in config.h, all.sh and
other places, which could be confusing. Just use tinycrypt everywhere because
that's the name of the project and repo where we took the files.

The changes were made using the following commands (with GNU sed and zsh):

sed -i 's/uecc/tinycrypt/g' **/*.[ch] tests/scripts/all.sh
sed -i 's/MBEDTLS_USE_UECC/MBEDTLS_USE_TINYCRYPT/g' **/*.[ch] tests/scripts/all.sh scripts/config.pl
diff --git a/include/mbedtls/check_config.h b/include/mbedtls/check_config.h
index e73beac..43f68de 100644
--- a/include/mbedtls/check_config.h
+++ b/include/mbedtls/check_config.h
@@ -87,8 +87,8 @@
 #error "MBEDTLS_CMAC_C defined, but not all prerequisites"
 #endif
 
-#if defined(MBEDTLS_USE_UECC) && defined(MBEDTLS_NO_64BIT_MULTIPLICATION)
-#error "MBEDTLS_USE_UECC defined, but it cannot be defined with MBEDTLS_NO_64BIT_MULTIPLICATION"
+#if defined(MBEDTLS_USE_TINYCRYPT) && defined(MBEDTLS_NO_64BIT_MULTIPLICATION)
+#error "MBEDTLS_USE_TINYCRYPT defined, but it cannot be defined with MBEDTLS_NO_64BIT_MULTIPLICATION"
 #endif
 
 #if defined(MBEDTLS_NIST_KW_C) && \