style: fix missing spaces in control statements

Result of running 'hg m5style --skip-all --fix-control -a'.

tests: A test program for the new mwait implementation.

This is a simple test program for the new mwait implemenation. It is uses
m5threads to create to threads of execution in syscall emulation mode that
interact using the mwait instruction.

Committed by: Nilay Vaish <nilay@cs.wisc.edu>