allow ./configure --disable-assert

[Eric Blake]

The branch currently only uses assert() inside gnulib, in contrast to head, but 
I figured it would be worth backporting this patch to the branch.

2007-06-26  Eric Blake  <address@hidden>

        * m4/gnulib-cache.m4: Augment with 'gnulib-tool --import assert'.

Index: m4/gnulib-cache.m4
===================================================================
RCS file: /sources/m4/m4/m4/Attic/gnulib-cache.m4,v
retrieving revision 1.1.2.27
diff -u -p -r1.1.2.27 gnulib-cache.m4
--- m4/gnulib-cache.m4  29 May 2007 13:19:47 -0000      1.1.2.27
+++ m4/gnulib-cache.m4  26 Jun 2007 15:31:20 -0000
@@ -15,11 +15,11 @@
 
 
 # Specification in the form of a command-line invocation:
-#   gnulib-tool --import --dir=. --lib=libm4 --source-base=lib --m4-base=m4 --
doc-base=doc --aux-dir=. --with-tests --no-libtool --macro-prefix=M4 avltree-
oset binary-io clean-temp cloexec close-stream closein config-h error fdl 
fflush fopen-safer free fseeko gendocs getopt gnupload mkstemp obstack regex 
stdbool stdint stdlib-safer strtol unlocked-io vasprintf-posix verror version-
etc-fsf xalloc xvasprintf
+#   gnulib-tool --import --dir=. --lib=libm4 --source-base=lib --m4-base=m4 --
doc-base=doc --aux-dir=. --with-tests --no-libtool --macro-prefix=M4 assert 
avltree-oset binary-io clean-temp cloexec close-stream closein config-h error 
fdl fflush fopen-safer free fseeko gendocs getopt gnupload mkstemp obstack 
regex stdbool stdint stdlib-safer strtol unlocked-io vasprintf-posix verror 
version-etc-fsf xalloc xvasprintf
 
 # Specification in the form of a few gnulib-tool.m4 macro invocations:
 gl_LOCAL_DIR([])
-gl_MODULES([avltree-oset binary-io clean-temp cloexec close-stream closein 
config-h error fdl fflush fopen-safer free fseeko gendocs getopt gnupload 
mkstemp obstack regex stdbool stdint stdlib-safer strtol unlocked-io vasprintf-
posix verror version-etc-fsf xalloc xvasprintf])
+gl_MODULES([assert avltree-oset binary-io clean-temp cloexec close-stream 
closein config-h error fdl fflush fopen-safer free fseeko gendocs getopt 
gnupload mkstemp obstack regex stdbool stdint stdlib-safer strtol unlocked-io 
vasprintf-posix verror version-etc-fsf xalloc xvasprintf])
 gl_AVOID([])
 gl_SOURCE_BASE([lib])
 gl_M4_BASE([m4])