libtool: merge some patches from yocto for cross builds.

srcpkgs/libtool/patches/0004-use-sysroot-in-libpath.patch

@@ -0,0 +1,18 @@
+When using sysroot we should append it to libdir, which is helpful in
+cross builds as the system is staged in the sysroot. For normal builds,
+i.e. when lt_sysroot is not set, it will still behave the same and add
+-L/usr/lib to the relink command.
+
+-Khem Raj <raj.khem@gmail.com>
+
+--- libltdl/config/ltmain.m4sh
++++ libltdl/config/ltmain.m4sh
+@@ -6122,7 +6122,7 @@ func_mode_link ()
+ 	      fi
+ 	    else
+ 	      # We cannot seem to hardcode it, guess we'll fake it.
+-	      add_dir="-L$libdir"
++	      add_dir="-L$lt_sysroot$libdir"
+ 	      # Try looking first in the location we're being installed to.
+ 	      if test -n "$inst_prefix_dir"; then
+ 		case $libdir in