perf: RISC-V: Eliminate redundant interrupt enable/disable operations

perf: RISC-V: Eliminate redundant interrupt enable/disable operations

The interrupt enable/disable operations are already performed by the
IRQ chip functions riscv_intc_irq_unmask()/riscv_intc_irq_mask() during
enable_percpu_irq()/disable_percpu_irq(). It can be done only once.

Signed-off-by: Yu Chien Peter Lin <peterlin@andestech.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
Link: https://lore.kernel.org/r/20240222083946.3977135-7-peterlin@andestech.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>