wcnss: fix the potential buffer overflow in wlan ctrl data process

Validate the userspace wlan control cmd data, info and length
before copy into wcnss driver buffer. Avoid unnecessary string
manipulation and use kernel defined format specifier to print
wlan MAC address.

CRs-Fixed: 2149331
Change-Id: Ib59fdcc0e6b84cdd73972dcb62b2c05e4741f5f7
Signed-off-by: Yuanyuan Liu <yuanliu@codeaurora.org>
Signed-off-by: Sarada Prasanna Garnayak <sgarna@codeaurora.org>