mm/huge_memory.c: make __thp_get_unmapped_area static

__thp_get_unmapped_area is only used in mm/huge_memory.c.  Make it static.
Tested by building and booting the kernel.

Link: http://lkml.kernel.org/r/20190504102353.GA22525@bharath12345-Inspiron-5559Signed-off-by: NBharath Vedartham <linux.bhar@gmail.com>
Acked-by: NMichal Hocko <mhocko@suse.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

mm/huge_memory.c

@@ -509,7 +509,7 @@ void prep_transhuge_page(struct page *page)
 	set_compound_page_dtor(page, TRANSHUGE_PAGE_DTOR);
 }
 
-unsigned long __thp_get_unmapped_area(struct file *filp, unsigned long len,
+static unsigned long __thp_get_unmapped_area(struct file *filp, unsigned long len,
 		loff_t off, unsigned long flags, unsigned long size)
 {
 	unsigned long addr;