Move ptid.h to common-defs.h

Move ptid.h to common-defs.h

This commit moves the inclusion of ptid.h to common-defs.h and removes
all other inclusions.

gdb/
2014-08-07  Gary Benson  <gbenson@redhat.com>

	* common/common-defs.h: Include ptid.h.
	* defs.h: Do not include ptid.h.
	* inferior.h: Likewise.
	* infrun.h: Likewise.
	* nat/linux-btrace.h: Likewise.
	* nat/linux-osdata.h: Likewise.
	* target/waitstatus.h: Likewise.

gdb/gdbserver/
2014-08-07  Gary Benson  <gbenson@redhat.com>

	* server.h: Do not include ptid.h.
	* notif.h: Likewise.