[9610] wlbt: Fix compilation errors Android P mxconf.c (Android P)

[9610] wlbt: Fix compilation errors Android P mxconf.c (Android P)

drivers/misc/samsung/scsc/mxman.c: In function 'mxman_init':
drivers/misc/samsung/scsc/mxman.c:1686:2: error: implicit declaration of function 'wlbtd_wq_init' [-Werror=implicit-function-declaration]
  wlbtd_wq_init(mxman);
  ^
drivers/misc/samsung/scsc/mxman.c: In function 'mxman_deinit':
drivers/misc/samsung/scsc/mxman.c:1706:2: error: implicit declaration of function 'wlbtd_wq_deinit' [-Werror=implicit-function-declaration]
  wlbtd_wq_deinit(mxman);
  ^
cc1: some warnings being treated as errors
scripts/Makefile.build:328: recipe for target 'drivers/misc/samsung/scsc/mxman.o' failed

Change-Id: I17248e84a4ecf9a0fbeef8ef5030def157fa808b
SCSC-Bug-Id: SSB-40175
Signed-off-by: Tarun Karela <t.karela@samsung.com>