Use target_desc fields expedite_regs and xmltarget ifndef IN_PROCESS_AGENT

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.

gdb/gdbserver:

2017-06-29  Yao Qi  <yao.qi@linaro.org>

	* tdesc.h (struct target_desc) [IN_PROCESS_AGENT] <expedite_regs>:
	Remove.
	[IN_PROCESS_AGENT] <xmltarget>: Likewise.

gdb:

2017-06-29  Yao Qi  <yao.qi@linaro.org>

	* regformats/regdat.sh: Generate code with
	"ifndef IN_PROCESS_AGENT".