i965: Drop the missing symbols link test.

This was horribly broken and has cost everyone more time than we were
ever going to save using it.  It might have been fixable, but the
problem it was originally trying to solve can be better solved with
-Werror=missing-prototypes and -Werror=implicit-function-declaration.

Also, it was always producing a big scary warning about how the link
test was non-portable.

Reviewed-by: Matt Turner <mattst88@gmail.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=44928

src/mesa/drivers/dri/i965/Makefile.am

@@ -58,15 +58,6 @@ i965_dri_la_LIBADD = \
 	$(INTEL_LIBS) \
 	../common/libdricommon.la
 
-# Test build to make sure that we didn't leave any undefined symbols in the
-# driver.
-noinst_PROGRAMS = i965_symbols_test
-
-i965_symbols_test_SOURCES = \
-	../common/dri_test.c
-i965_symbols_test_LDADD = \
-	i965_dri.la
-
 # Provide compatibility with scripts for the old Mesa build system for
 # a while by putting a link to the driver into /lib of the build tree.
 all-local: i965_dri.la