Revert "ARM: 7526/1: traps: send SIGILL if get_user fails on undef handling path"

This reverts commit 7e4a7b92f9a7649a42ccd5fd6e66f34431499b65.
Revert "irq_work: Make self-IPIs optable"

This reverts commit ab804bb5bbdb9cead37173cddb7f2e65655c3037.