Revert "block: fifo-iosched.c: fix compiling"

This reverts commit 063730495c56e361e12721e805f1c87bdff9a0dc.

Conflicts:

	arch/arm/configs/metallice_grouper_defconfig
Revert "Add FIFO scheduler"

This reverts commit 737d837d35044b18ace3d5830b7aa1da44a7da94.