cnss2: Dump WLAON registers for QCA6490 device

Add support to dump WLAON registers for QCA6490 device. Rename
WLAON registers to common names since most of them are same across
resent devices. Add device mask for these registers so that they
can be dumped selectively for each device.

Change-Id: I5dfe8350c3449b9bfbdbce637527cb2eb199519a
Signed-off-by: Yue Ma <yuem@codeaurora.org>