build: remove glibc backcompat requirement for Linux symbol checks

Author: fanquake

src/Makefile.am

@@ -822,7 +822,7 @@ if TARGET_WINDOWS
 	$(AM_V_at) OBJDUMP=$(OBJDUMP) $(PYTHON) $(top_srcdir)/contrib/devtools/symbol-check.py $(bin_PROGRAMS)
 endif
 
-if GLIBC_BACK_COMPAT
+if TARGET_LINUX
 	@echo "Checking glibc back compat..."
 	$(AM_V_at) CPPFILT=$(CPPFILT) $(PYTHON) $(top_srcdir)/contrib/devtools/symbol-check.py $(bin_PROGRAMS)
 endif