ANDROID: mm: allow hooks into __alloc_pages()

Allow drivers to register mm_page_alloc hooks when alloc pages.
This helps to get page info when alloc pages exit.

Bug: 307485594
Change-Id: I6bdec48bf04a19718e49a51e52ac8d4ae64a7f86
Signed-off-by: Qinglin Li <qinglin.li@amlogic.com>

mm/page_alloc.c

@@ -81,6 +81,8 @@
 #include "shuffle.h"
 #include "page_reporting.h"
 
+EXPORT_TRACEPOINT_SYMBOL_GPL(mm_page_alloc);
+
 /* Free Page Internal flags: for internal, non-pcp variants of free_pages(). */
 typedef int __bitwise fpi_t;