wil6210: change reply_size arg to u16 in wmi_call

Change the type of the argument reply_size from u8 to
u16 in order to support reply sizes > 255 bytes.
The driver already supports u16 reply size in all
other places, this was the only missing change.

Change-Id: I0e9baafdc50d845036e5f2b50c0b55935eb09082
Signed-off-by: Lior David <liord@codeaurora.org>
Signed-off-by: Maya Erez <merez@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Git-commit: 5f85c7e702d2185d3d553982f916b5ac96ae77a9
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/kvalo/ath.git