Update references to old Github organisation

Replace references to ARMmbed organisation with the new
org, Mbed-TLS, following project migration.

Signed-off-by: Dave Rodgman <dave.rodgman@arm.com>
diff --git a/tests/suites/test_suite_pk.data b/tests/suites/test_suite_pk.data
index 9ebdc7e..d3594b8 100644
--- a/tests/suites/test_suite_pk.data
+++ b/tests/suites/test_suite_pk.data
@@ -287,7 +287,7 @@
 depends_on:MBEDTLS_ECP_DP_SECP192K1_ENABLED
 pk_psa_sign:MBEDTLS_ECP_DP_SECP192K1:PSA_ECC_FAMILY_SECP_K1:192
 
-## Currently buggy: https://github.com/ARMmbed/mbed-crypto/issues/336
+## Currently buggy: https://github.com/Mbed-TLS/mbed-crypto/issues/336
 # PSA wrapped sign: SECP224K1
 # depends_on:MBEDTLS_ECP_DP_SECP224K1_ENABLED
 # pk_psa_sign:MBEDTLS_ECP_DP_SECP224K1:PSA_ECC_FAMILY_SECP_K1:224
diff --git a/tests/suites/test_suite_pk.function b/tests/suites/test_suite_pk.function
index 82d1573..10a7f81 100644
--- a/tests/suites/test_suite_pk.function
+++ b/tests/suites/test_suite_pk.function
@@ -12,7 +12,7 @@
 
 /* Needed only for test case data under #if defined(MBEDTLS_USE_PSA_CRYPTO),
  * but the test code generator requires test case data to be valid C code
- * unconditionally (https://github.com/ARMmbed/mbedtls/issues/2023). */
+ * unconditionally (https://github.com/Mbed-TLS/mbedtls/issues/2023). */
 #include "psa/crypto.h"
 
 #define RSA_KEY_SIZE 512