ANDROID: vendor_hooks: shorten mutex_unlock_slowpath_before_wakeq

When we use this KMI(__tracepoint_android_vh_mutex_unlock_slowpath_before_wakeq)
in vendor modules, it reports modpost error: too long symbol. So, shorten it as
__tracepoint_android_vh_mutex_unlock_slowpath_bf_wakeq.

Fixes: 9f6bd037 ("ANDROID: vendor_hooks: add hook in __mutex_unlock_slowpath()")

Bug: 388166014
Bug: 381511799

Change-Id: I1a74ea3433dd2d9e234f56ea81a7c1020f4a56bb
Signed-off-by: wei li <sirius.liwei@honor.corp-partner.google.com>
(cherry picked from commit e0a26bcd)