Revert "Revert "Revert "omap4: cpuidle: Some obvious optimisations to the code path"""

This reverts commit 7e68e53179cd26e73badb8adc9919b610695da27.
Revert "Revert "Revert "omap44xx: cpuidle: Update target residencies to saner values"""

This reverts commit 83a94c3b93cc1514333fd0d5d72585b050dc7808.
Revert "Revert "Revert "cpuidle: Add last_residency trace event for residency profiling"""

This reverts commit 3f55b78b8e80e4f1d689cc8989baa512d237e03f.