Merge pull request #375 from dgarske/stm32hashfixes

Fixes when using the STM32 with STM32F2_HASH defined.

wolfcrypt/src/md5.c

@@ -64,6 +64,7 @@
      * document (See note in README).
      */
     #include "stm32f2xx.h"
+    #include "stm32f2xx_hash.h"
 
     void wc_InitMd5(Md5* md5)
     {

wolfcrypt/src/sha.c

@@ -136,7 +136,7 @@ int wc_ShaUpdate(Sha* sha, const byte* data, word32 len)
             /* append partial to existing stored block */
             XMEMCPY((byte*)sha->buffer + sha->buffLen, data, len);
             sha->buffLen += len;
-            return;
+            return 0;
         }
     }