Changed every memcpy to SCA equivalent mbedtls_platform_memcpy

This makes physical attacks more difficult.
diff --git a/library/pkcs12.c b/library/pkcs12.c
index 85eb31e..39db2df 100644
--- a/library/pkcs12.c
+++ b/library/pkcs12.c
@@ -239,7 +239,7 @@
     while( data_len > 0 )
     {
         use_len = ( data_len > fill_len ) ? fill_len : data_len;
-        memcpy( p, filler, use_len );
+        mbedtls_platform_memcpy( p, filler, use_len );
         p += use_len;
         data_len -= use_len;
     }
@@ -315,7 +315,7 @@
         }
 
         use_len = ( datalen > hlen ) ? hlen : datalen;
-        memcpy( p, hash_output, use_len );
+        mbedtls_platform_memcpy( p, hash_output, use_len );
         datalen -= use_len;
         p += use_len;