configure: allow to disable libnss and libnspr

Let user chose to disable libnss and libnspr support even if these
libraries are installed in the system. Default remains to enable when
libraries are found and disable parameter were not used

configure.ac

@@ -1586,8 +1586,16 @@
     fi
 
   # libnspr
-    enable_nspr="no"
+    AC_ARG_ENABLE(nspr,
+            AS_HELP_STRING([--disable-nspr],[Disable libnspr support]))
+    AC_ARG_WITH(libnspr_includes,
+            [  --with-libnspr-includes=DIR  libnspr include directory],
+            [with_libnspr_includes="$withval"],[with_libnspr_includes=no])
+    AC_ARG_WITH(libnspr_libraries,
+            [  --with-libnspr-libraries=DIR    libnspr library directory],
+            [with_libnspr_libraries="$withval"],[with_libnspr_libraries="no"])
 
+    if test "$enable_nspr" != "no"; then
       # Try pkg-config first:
       PKG_CHECK_MODULES([libnspr], nspr,, [with_pkgconfig_nspr=no])
       if test "$with_pkgconfig_nspr" != "no"; then
@@ -1595,13 +1603,6 @@
           LIBS="${LIBS} ${libnspr_LIBS}"
       fi
 
-    AC_ARG_WITH(libnspr_includes,
-            [  --with-libnspr-includes=DIR  libnspr include directory],
-            [with_libnspr_includes="$withval"],[with_libnspr_includes=no])
-    AC_ARG_WITH(libnspr_libraries,
-            [  --with-libnspr-libraries=DIR    libnspr library directory],
-            [with_libnspr_libraries="$withval"],[with_libnspr_libraries="no"])
-
       if test "$with_libnspr_includes" != "no"; then
           CPPFLAGS="${CPPFLAGS} -I${with_libnspr_includes}"
       fi
@@ -1626,10 +1627,19 @@
           fi
           enable_nspr="yes"
       fi
+    fi
 
   # libnss
-    enable_nss="no"
+    AC_ARG_ENABLE(nss,
+            AS_HELP_STRING([--disable-nss],[Disable libnss support]))
+    AC_ARG_WITH(libnss_includes,
+            [  --with-libnss-includes=DIR  libnss include directory],
+            [with_libnss_includes="$withval"],[with_libnss_includes=no])
+    AC_ARG_WITH(libnss_libraries,
+            [  --with-libnss-libraries=DIR    libnss library directory],
+            [with_libnss_libraries="$withval"],[with_libnss_libraries="no"])
 
+    if test "$enable_nss" != "no"; then
       # Try pkg-config first:
       PKG_CHECK_MODULES([libnss], nss,, [with_pkgconfig_nss=no])
       if test "$with_pkgconfig_nss" != "no"; then
@@ -1637,13 +1647,6 @@
           LIBS="${LIBS} ${libnss_LIBS}"
       fi
 
-    AC_ARG_WITH(libnss_includes,
-            [  --with-libnss-includes=DIR  libnss include directory],
-            [with_libnss_includes="$withval"],[with_libnss_includes=no])
-    AC_ARG_WITH(libnss_libraries,
-            [  --with-libnss-libraries=DIR    libnss library directory],
-            [with_libnss_libraries="$withval"],[with_libnss_libraries="no"])
-
       if test "$with_libnss_includes" != "no"; then
           CPPFLAGS="${CPPFLAGS} -I${with_libnss_includes}"
       fi
@@ -1670,6 +1673,7 @@
           AC_DEFINE([HAVE_NSS],[1],[libnss available for md5])
           enable_nss="yes"
       fi
+    fi
 
   # libmagic
     enable_magic="no"