tests: avoid false failure in cygnus-dependency-tracking.test.

[Ralf Wildenhues]

This is what GCC 3.4.6 on FreeBSD prints:

foo.c: In function `main':
foo.c:4: error: syntax error before numeric constant

I'll push the fix below.

Cheers,
Ralf

    tests: avoid false failure in cygnus-dependency-tracking.test.
    
    * tests/cygnus-dependency-tracking.test: Be less restrictive
    when grepping the compiler error message, GCC 3.4.6 on FreeBSD
    does not mention an undefined symbol.

diff --git a/tests/cygnus-dependency-tracking.test 
b/tests/cygnus-dependency-tracking.test
index 5f0051e..1bfec25 100755
--- a/tests/cygnus-dependency-tracking.test
+++ b/tests/cygnus-dependency-tracking.test
@@ -66,6 +66,7 @@ $MAKE test-nodeps
 $MAKE clean
 $MAKE >out 2>&1 && { cat out; Exit 1; }
 cat out
-$FGREP 'GIVE_BACK' out
+# Not all compilers mention the undefined symbol in the error message.
+grep GIVE_BACK out || grep main out
 
 :