rbtree, uprobes: Use rbtree helpers

mainline inclusion
from mainline-v5.12-rc1
commit a905e84e
category: feature
feature: SPR PMU uncore support
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I5BECO



Intel-SIG: commit a905e84e rbtree, uprobes: Use rbtree helpers
This commit is backported as a dependency for SPR PMU uncore support.

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Reduce rbtree boilerplate by using the new helpers.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Yunying Sun <yunying.sun@intel.com>
Signed-off-by: Aichun Shi <aichun.shi@intel.com>