Fix SHA definitions and their dependencies in library and test suites.

Rework SHA224 and SHA283 documentation.
Define MBEDTLS_SHAxxx_C options in alphabetic order.
Fix SHA224 and SHA384 dependencies in test suites.

Signed-off-by: Mateusz Starzyk <mateusz.starzyk@mobica.com>
diff --git a/configs/config-thread.h b/configs/config-thread.h
index 1deb8a5..3314037 100644
--- a/configs/config-thread.h
+++ b/configs/config-thread.h
@@ -67,8 +67,8 @@
 #define MBEDTLS_OID_C
 #define MBEDTLS_PK_C
 #define MBEDTLS_PK_PARSE_C
-#define MBEDTLS_SHA256_C
 #define MBEDTLS_SHA224_C
+#define MBEDTLS_SHA256_C
 #define MBEDTLS_SSL_COOKIE_C
 #define MBEDTLS_SSL_CLI_C
 #define MBEDTLS_SSL_SRV_C