build: link curl to NSS libraries when NSS support is enabled

This fixes a build failure on Debian caused by commit
24c3cdce.

Bug: http://curl.haxx.se/mail/lib-2014-07/0209.html

RELEASE-NOTES

@@ -12,6 +12,7 @@ This release includes the following changes:
 
 This release includes the following bugfixes:
 
+ o fix a build failure on Debian when NSS support is enabled [1]
  o 
 
 This release includes the following known bugs:
@@ -27,4 +28,4 @@ advice from friends like these:
 
 References to bug reports and discussions on issues:
 
- [1] = 
+ [1] = http://curl.haxx.se/mail/lib-2014-07/0209.html

configure.ac

@@ -2078,6 +2078,10 @@ if test "$curl_ssl_msg" = "$init_ssl_msg"; then
       if test "x$USE_NSS" = "xyes"; then
         AC_MSG_NOTICE([detected NSS version $version])
 
+        dnl needed when linking the curl tool without USE_EXPLICIT_LIB_DEPS
+        NSS_LIBS=$addlib
+        AC_SUBST([NSS_LIBS])
+
         dnl when shared libs were found in a path that the run-time
         dnl linker doesn't search through, we need to add it to
         dnl LD_LIBRARY_PATH to prevent further configure tests to fail

src/Makefile.am

@@ -62,7 +62,7 @@ LIBS = $(BLANK_AT_MAKETIME)
 if USE_EXPLICIT_LIB_DEPS
 curl_LDADD = $(top_builddir)/lib/libcurl.la @LIBMETALINK_LIBS@ @LIBCURL_LIBS@
 else
-curl_LDADD = $(top_builddir)/lib/libcurl.la @LIBMETALINK_LIBS@ @ZLIB_LIBS@ @CURL_NETWORK_AND_TIME_LIBS@
+curl_LDADD = $(top_builddir)/lib/libcurl.la @LIBMETALINK_LIBS@ @NSS_LIBS@ @ZLIB_LIBS@ @CURL_NETWORK_AND_TIME_LIBS@
 endif
 
 curl_LDFLAGS = @LIBMETALINK_LDFLAGS@