arm64: cpufeatures: use min and max

Use min and max to make the effect more clear.

Generated by: scripts/coccinelle/misc/minmax.cocci

CC: Denis Efremov <efremov@linux.com>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: kernel test robot <lkp@intel.com>
Signed-off-by: Julia Lawall <julia.lawall@inria.fr>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/alpine.DEB.2.22.394.2104292246300.16899@hadrien


[catalin.marinas@arm.com: include <linux/minmax.h> explicitly]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>