brcmsmac: Use debug macros for general error and debug statements

Convert most uses of wiphy_* and pr_* for general error and debug
messages to use the internal debug macros instead. Most code used only
for initialization still use wiphy_err(), as well as some locations
which are executed too early to use the debug macros. Some debug
messages which are redundant or not useful are removed.

Acked-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Tested-by: Daniel Wagner <wagi@monom.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>