tdf#122221: Bin apparently unnecessary early return

Removing these few lines of code fixes the problem on iOS, as far as I
can see. Let's hope it doesn't introduce any new issue in the iOS app.
In this branch, I didn't have the clout to remove them for macOS, too.

Change-Id: I2380d010ba223a698acfe916fca4580a1502be98

vcl/quartz/salgdicommon.cxx

@@ -571,11 +571,13 @@ bool AquaSalGraphics::drawAlphaBitmap( const SalTwoRect& rTR,
                                        const SalBitmap& rSrcBitmap,
                                        const SalBitmap& rAlphaBmp )
 {
+#ifndef IOS
     if (rTR.mnSrcWidth != rTR.mnDestWidth || rTR.mnSrcHeight != rTR.mnDestHeight)
     {
         // TODO - would be better to scale it by the native code
         return false;
     }
+#endif
 
     // An image mask can't have a depth > 8 bits (should be 1 to 8 bits)
     if( rAlphaBmp.GetBitCount() > 8 )