Experimental change commited to the wrong branch - reverting

Revert "kernel: Implement vectorized interrupt support (patch from WL500g/OpenWRT)"

This reverts commit 895b0da4d0d2a73bdc625a6fd276a0b2a918ff3b.
Experimental change commited to the wrong branch - reverting

Revert "kernel: Switch allocator from SLAB to SLUB to match ARM platform"

This reverts commit 7cd3bb3c1474cd0ca65e3c5dd46af87fa8025ccb.