Remove SP_CFLAGS and SP_LDFLAGS

SP_CFLAGS and SP_LDFLAGS are only used as initial values for ARCH_CFLAGS/ARCH_LDFLAGS.  Call it directly ARCH_*.  Once there, use the same indentantion that the rest of the file

Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>