Forgot about ALL_TARGET_OBS:

gdb/ChangeLog
2015-07-15  Aleksandar Ristovski  <aristovski@qnx.com
	    Jan Kratochvil  <jan.kratochvil@redhat.com>

	Create empty nat/linux-maps.[ch] and common/target-utils.[ch].
	* Makefile.in (ALL_TARGET_OBS): Add linux-maps.o.
	(HFILES_NO_SRCDIR); Add nat/linux-maps.h,
	common/target-utils.h.
	(COMMON_OBS): Add target-utils.o.
	(linux-maps.o, target-utils.o): New.
	* target/target-utils.c: New file.
	* target/target-utils.h: New file.
	* nat/linux-maps.c: New file.
	* nat/linux-maps.h: New file.
	* configure.tgt (aarch64*-*-linux*, alpha*-*-linux*)
	(am33_2.0*-*-linux*, arm*-*-linux*, bfin-*-*linux*, cris*, frv-*-*)
	(hppa*-*-linux*, i[34567]86-*-linux*, ia64-*-linux*, m32r*-*-linux*)
	(m68*-*-linux*, microblaze*-linux-*, microblaze*-*-linux*)
	(mips*-*-linux*, nios2*-*-linux*, powerpc*-*-linux*, s390*-*-linux*)
	(sh*-*-linux*, sparc-*-linux*, sparc64-*-linux*, tic6x-*-*linux)
	(tilegx-*-linux*, x86_64-*-linux*, xtensa*-*-linux*): Add linux-maps.o
	to gdb_target_obs.

gdb/gdbserver/ChangeLog
2015-07-15  Aleksandar Ristovski  <aristovski@qnx.com
	    Jan Kratochvil  <jan.kratochvil@redhat.com>

	Create empty nat/linux-maps.[ch] and common/target-utils.[ch].
	* Makefile.in (OBS): Add target-utils.o.
	(linux-maps.o, target-utils.o): New.
	* configure.srv (srv_linux_obj): Add linux-maps.o.