perf: arm_v7_pmu: Drop obvious comments for enabling/disabling counters and interrupts

The function calls for enabling/disabling counters and interrupts are
pretty obvious as to what they are doing, and the comments don't add
any additional value.

Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Tested-by: James Clark <james.clark@linaro.org>
Link: https://lore.kernel.org/r/20250218-arm-brbe-v19-v20-4-4e9922fc2e8e@kernel.org


Signed-off-by: Will Deacon <will@kernel.org>