ANDROID: Allow vendor modules perform more operations on binder transaction.

Export binder_alloc_copy_from_buffer, allow vendor modules perform more operations
on binder transaction and improve user operation fluency and timeliness experience.

Bug: 343139379
Change-Id: I4353763099d854a62d0b70b003fbaca00e2c76e4
Signed-off-by: Dezhi Huang <huangdezhi@hihonor.com>
(cherry picked from commit d8db83d94e14b48819bba18cb975943c237e33df)

drivers/android/binder_alloc.c

@@ -1305,3 +1305,4 @@ int binder_alloc_copy_from_buffer(struct binder_alloc *alloc,
 	return binder_alloc_do_buffer_copy(alloc, false, buffer, buffer_offset,
 					   dest, bytes);
 }
+EXPORT_SYMBOL_GPL(binder_alloc_copy_from_buffer);