ALSA: usb: qcom: Fix false-positive address space check

The sanity check previously added to uaudio_transfer_buffer_setup()
assumed the allocated buffer being linear-mapped.  But the buffer
allocated via usb_alloc_coherent() isn't always so, rather to be used
with (SG-)DMA API.  This leaded to a false-positive warning and the
driver failed to work.

Actually uaudio_transfer_buffer_setup() deals only with the DMA-API
addresses for MEM_XFER_BUF type, while other callers of
uaudio_iommu_map() are with pages with physical addresses for
MEM_EVENT_RING and MEM_XFER_RING types.  So this patch splits the
mapping helper function to two different ones, uaudio_iommu_map() for
the DMA pages and uaudio_iommu_map_pa() for the latter, in order to
handle mapping differently for each type.  Along with it, the
unnecessary address check that caused probe error is dropped, too.

Fixes: 3335a1bbd624 ("ALSA: qc_audio_offload: try to reduce address space confusion")
Suggested-by: Arnd Bergmann <[email protected]>
Acked-by: Arnd Bergmann <[email protected]>
Reported-and-tested-by: Luca Weiss <[email protected]>
Closes: https://lore.kernel.org/[email protected]
Signed-off-by: Takashi Iwai <[email protected]>

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