gdi32: Use supplied hdc for DIB_RGB_COLORS if it's valid

[Nikolay Sivov]

This is about to fix regression introduced with 2854884a428e222cbb9078d875068a72f25365c4.

Initial patch fixed MSVS 2005 toolbars blackness, this one doesn't break a fix,
and fixes regressed Animation control glitches (and probably reported games related problems).