Use target_desc fields expedite_regs and xmltarget ifndef IN_PROCESS_AGENT
struct target_desc is used by both GDBserver and IPA, but fields
expedite_regs and xmltarget are only used in GDBserver, so this patch wraps
these two fields by ifndef IN_PROCESS_AGENT. This patch also changes
regformats/regdat.sh to generate .c files in this way too.