dsound: Sign-compare warnings fix

[Andrew Talbot]

Changelog:
    dsound: Sign-compare warnings fix.

diff --git a/dlls/dsound/capture.c b/dlls/dsound/capture.c
index 7cf7b83..d84a8fe 100644
--- a/dlls/dsound/capture.c
+++ b/dlls/dsound/capture.c
@@ -386,7 +386,7 @@ DirectSoundCaptureEnumerateW(
 
 static void capture_CheckNotify(IDirectSoundCaptureBufferImpl *This, DWORD from, DWORD len)
 {
-    unsigned i;
+    int i;
     for (i = 0; i < This->nrofnotifies; ++i) {
         LPDSBPOSITIONNOTIFY event = This->notifies + i;
         DWORD offset = event->dwOffset;
diff --git a/dlls/dsound/mixer.c b/dlls/dsound/mixer.c
index 3c13e8f..efcb21b 100644
--- a/dlls/dsound/mixer.c
+++ b/dlls/dsound/mixer.c
@@ -324,7 +324,8 @@ static inline DWORD DSOUND_BufPtrDiff(DWORD buflen, DWORD ptr1, DWORD ptr2)
  */
 void DSOUND_MixToTemporary(const IDirectSoundBufferImpl *dsb, DWORD writepos, DWORD len, BOOL inmixer)
 {
-	INT	i, size;
+	DWORD	i;
+	INT	size;
 	BYTE	*ibp, *obp, *obp_begin;
 	INT	iAdvance = dsb->pwfx->nBlockAlign;
 	INT	oAdvance = dsb->device->pwfx->nBlockAlign;