rcu: Rename note_new_gpnum() to note_gp_changes()

Because note_new_gpnum() now also checks for the ends of old grace periods,
this commit changes its name to note_gp_changes().  Later commits will merge
rcu_process_gp_end() into note_gp_changes().

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git


Git-commit: d34ea3221a0f34ed42eadabf054604bbcc7ecd27
Signed-off-by: Kishan Kumar <kishank@codeaurora.org>