fs/proc/inode.c: annotate close_pdeo() for sparse

Fix sparse locking imbalance warning:

	warning: context imbalance in close_pdeo() - unexpected unlock

Link: http://lkml.kernel.org/r/20200227201538.GA30462@avx2
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>

fs/proc/inode.c

@@ -139,6 +139,7 @@ static void unuse_pde(struct proc_dir_entry *pde)
 
 /* pde is locked on entry, unlocked on exit */
 static void close_pdeo(struct proc_dir_entry *pde, struct pde_opener *pdeo)
+	__releases(&pde->pde_unload_lock)
 {
 	/*
 	 * close() (proc_reg_release()) can't delete an entry and proceed: