wil6210: remove "No Snoop" settings for RX transactions

"No Snoop" for RX transactions was previously set as a WA for a
PCIe HW issue. As the PCIe HW issue is fixed, the WA no longer
required.
Removal of the "No Snoop" bit will allow enabling DMA coherency
when SMMU is enabled.

Change-Id: I2030ea7182316ae18483ffb79d0a1de4d90f2fda
Signed-off-by: Maya Erez <merez@codeaurora.org>