Do not defer softirq processing when RT throttling.
Otherwise softirq process would be deferred indefinitely.
Bug: 234597245
Test: Trigger RT Throttling and check RT & softirq behavior
Fixes: "ANDROID: softirq: defer softirq processing to ksoftirqd if CPU is busy with RT"
Signed-off-by: Luke Chang <lukechang@google.com>
Change-Id: I76df270c39ce8c0633b914c3354a27d6e559ec94
(cherry picked from commit e913814ab623277ce87528d2957709f2ad748641)