ct-ng: Add ability to configure and use some GNU tools

Make the paths to libtool, objcopy, objdump, readelf, patch configurable.

Makefile.in

@@ -52,6 +52,11 @@ bash   := @@bash@@
 grep   := @@grep@@
 make   := @@make@@
 sed    := @@sed@@
+libtool:= @@libtool@@
+objcopy:= @@objcopy@@
+objdump:= @@objdump@@
+readelf:= @@readelf@@
+patch  := @@patch@@
 
 ###############################################################################
 # Sanity checks
@@ -139,6 +144,11 @@ paths.mk:
 	  echo "export grep=$(grep)";       \
 	  echo "export make=$(make)";       \
 	  echo "export sed=$(sed)";         \
+	  echo "export libtool=$(libtool)"; \
+	  echo "export objcopy=$(objcopy)"; \
+	  echo "export objdump=$(objdump)"; \
+	  echo "export readelf=$(readelf)"; \
+	  echo "export patch=$(patch)";     \
 	 ) >paths.mk
 
 #--------------------------------------

configure

@@ -365,6 +365,10 @@ has_or_abort prog=gzip
 has_or_abort prog=bzip2
 has_or_abort prog=lzma
 has_or_abort prog=readlink
+has_or_abort prog=objcopy var=objcopy
+has_or_abort prog=objdump var=objdump
+has_or_abort prog=readelf var=readelf
+has_or_abort prog=patch var=patch
 
 has_or_abort inc="ncurses/ncurses.h ncurses/curses.h ncurses.h curses.h"    \
              err="'ncurses' headers files were not found"