[glib] build: Simplify dtrace configuration

[Philip Withnall <pwithnall src gnome org>]

commit 8c6d08ab1b8ec57b81d77d44820f40625009b2cc
Author: Philip Withnall <philip withnall collabora co uk>
Date:   Wed Jun 29 15:08:22 2016 +0100

    build: Simplify dtrace configuration
    
    Apply the same changes as in commit
    7563ab473468fecefc388ae2ed06afab8ead6211 to gio/Makefile.am.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=725902

 gio/Makefile.am |    5 +----
 1 files changed, 1 insertions(+), 4 deletions(-)
---
diff --git a/gio/Makefile.am b/gio/Makefile.am
index 33a73fb..0ed84b2 100644
--- a/gio/Makefile.am
+++ b/gio/Makefile.am
@@ -761,15 +761,12 @@ dist_its_DATA = gschema.loc gschema.its
 # SystemTap and dtrace
 
 if ENABLE_DTRACE
-DTCOMPILE = $(patsubst -W%,,$(LTCOMPILE))
-DTCFLAGS = $(patsubst -W%,,$(CFLAGS))
-
 gio_probes.h: gio_probes.d
        $(AM_V_GEN) $(DTRACE) -C -h -s $< -o $  tmp
        @$(SED) -e "s,define STAP_HAS_SEMAPHORES 1,undef STAP_HAS_SEMAPHORES," < $  tmp > $@ && rm -f $  tmp
 
 gio_probes.lo: gio_probes.d
-       $(AM_V_GEN) env CC="$(DTCOMPILE)" CFLAGS="$(DTCFLAGS)" $(DTRACE) -G -s $< -o $@
+       $(AM_V_GEN) $(LIBTOOL) --mode=compile $(AM_V_lt) --tag=CC $(DTRACE) -G -s $< -o $@
 
 BUILT_SOURCES += gio_probes.h gio_probes.lo
 CLEANFILES += gio_probes.h gio_probes.h.tmp