ALSA: pdaudiocf: Drop superfluous GFP setup

The extra setup with GFP_DMA32 is superfluous for this driver.  The
whole operation is a simple copy loop, and there is no memory address
restriction at all.  Drop the useless GFP setup.

Link: https://lore.kernel.org/r/20220823115740.14123-3-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>