Fixed const correctness issues that have no impact on the ABI
(cherry picked from commit eae09db9e57b7a342ea15bf57c5c1439c59a2e50)

Conflicts:
	library/gcm.c
diff --git a/library/md5.c b/library/md5.c
index b2ee10b..3097aeb 100644
--- a/library/md5.c
+++ b/library/md5.c
@@ -220,8 +220,7 @@
 
     if( left && ilen >= fill )
     {
-        memcpy( (void *) (ctx->buffer + left),
-                (void *) input, fill );
+        memcpy( (void *) (ctx->buffer + left), input, fill );
         md5_process( ctx, ctx->buffer );
         input += fill;
         ilen  -= fill;
@@ -237,8 +236,7 @@
 
     if( ilen > 0 )
     {
-        memcpy( (void *) (ctx->buffer + left),
-                (void *) input, ilen );
+        memcpy( (void *) (ctx->buffer + left), input, ilen );
     }
 }
 
@@ -269,7 +267,7 @@
     last = ctx->total[0] & 0x3F;
     padn = ( last < 56 ) ? ( 56 - last ) : ( 120 - last );
 
-    md5_update( ctx, (unsigned char *) md5_padding, padn );
+    md5_update( ctx, md5_padding, padn );
     md5_update( ctx, msglen, 8 );
 
     PUT_UINT32_LE( ctx->state[0], output,  0 );