Fixed build Visual Studio build warnings

Author: slouken

src/codecs/music_wavpack.c

@@ -584,7 +584,7 @@ static int WAVPACK_Seek(void *context, double time)
     int64_t sample = (int64_t)(time * music->samplerate);
     int success = (wvpk.WavpackSeekSample64 != NULL) ?
                    wvpk.WavpackSeekSample64(music->ctx, sample) :
-                   wvpk.WavpackSeekSample(music->ctx, sample);
+                   wvpk.WavpackSeekSample(music->ctx, (uint32_t)sample);
     if (!success) {
         return Mix_SetError("%s", wvpk.WavpackGetErrorMessage(music->ctx));
     }

src/codecs/music_xmp.c

@@ -191,10 +191,11 @@ static unsigned long xmp_fread(void *dst, unsigned long len, unsigned long nmemb
 static int xmp_fseek(void *src, long offset, int whence)
 {
     XMP_Music *music = (XMP_Music *)src;
+    Sint64 offset64 = (Sint64)offset;
     if (whence == RW_SEEK_SET) {
-        offset += music->src_offset;
+        offset64 += music->src_offset;
     }
-    return (SDL_RWseek(music->src, offset, whence) < 0) ? -1 : 0;
+    return (SDL_RWseek(music->src, offset64, whence) < 0) ? -1 : 0;
 }
 
 static long xmp_ftell(void *src)