block: Don't disable interrupts in trigger_softirq()

trigger_softirq() is always invoked as a SMP-function call which is
always invoked with disables interrupts.

Don't disable interrupt in trigger_softirq() because interrupts are
already disabled.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>