ath10k: Set DMA address mask to 35 bit for WCN3990

WCN3990 is a 37-bit target but can address memory range
only upto 35 bits. The 36th bit is used to control the
smmu/iommu translation and the 37th bit is used by the
internal bus masters to access the wifi subsystem internal
SRAM. With the DMA mask set to 37i-bit, the host driver
can get 37-bit dma address, which leads to incorrect
address access in the target.

Hence the host driver can used addresses upto 35-bit
for WCN3990. Fix the dma mask for wcn3990 to 35-bit,
instead of 37-bit.

Tested HW: WCN3990
Tested FW: WLAN.HL.2.0-01188-QCAHLSWMTPLZ-1

Tested-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Rakesh Pillai <pillair@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>