Consolidate compiler invocations (Avi Kivity)

Instead of specifying the compilation command over and over, use a single
rule and adjust it as necessary using target specific target overrides.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>


git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6377 c046a42c-6fe2-441c-8c8c-71466251a162
