lwlib/Makefile.in misc cleanup.

lwlib/Makefile.in misc cleanup.

* lwlib/Makefile.in (USE_X_TOOLKIT, RM, TOOLKIT_DEFINES): Remove.
(ALL_CFLAGS): Remove -I.
(config_h, lisp_h, src_h): New variables.
(globals_h): Rename from $globals.
($(globals_h)): Check cd exit status.
(lwlib.o): Remove special rule.
(lwlib-utils.o, lwlib.o, lwlib-Xlw.o, lwlib-Xaw.o, lwlib-Xm.o, xlwmenu.o):
Add lisp.h and config.h to prereqs.
(lwlib-utils.o): Add lwlib.h to prereqs.
(lwlib.o): Add lwlib-utils.h and lwlib-Xm.h to prereqs.
(lwlib-Xlw.o): Add xlwmenu.h to prereqs.
(xlwmenu.o): Add ../src/xterm.h to prereqs.
(mostlyclean): Forget about "core" files.