Fix description of AC_CHECK_LIB regarding other deplibs.

[Ralf Wildenhues]

Only static linking is fairly reliable in failing with forgotten other
libraries.  OK?

Thanks,
Ralf

    Fix description of AC_CHECK_LIB regarding other deplibs.

    * doc/autoconf.texi (Libraries): Library linking may not fail
    even without missing additional libs.

diff --git a/doc/autoconf.texi b/doc/autoconf.texi
index 6319024..e1358d8 100644
--- a/doc/autoconf.texi
+++ b/doc/autoconf.texi
@@ -4301,9 +4301,9 @@ Libraries
 If linking with @var{library} results in unresolved symbols that would
 be resolved by linking with additional libraries, give those libraries
 as the @var{other-libraries} argument, separated by spaces:
-e.g., @option{-lXt -lX11}.  Otherwise, this macro fails to detect
-that @var{library} is present, because linking the test program
-always fails with unresolved symbols.  The @var{other-libraries} argument
+e.g., @option{-lXt -lX11}.  Otherwise, this macro may fail to detect
+that @var{library} is present, because linking the test program can
+fail with unresolved symbols.  The @var{other-libraries} argument
 should be limited to cases where it is desirable to test for one library
 in the presence of another that is not already in @code{LIBS}.