[PATCH] fix headers_install for x86-64.

[Rob Landley <rob@landley.net>]

Signed-off-by: Rob Landley <rob@landley.net>

A bug in headers_install for ARCH=x86_64 yields an asm/ directory full of 
files all of which are using the same #ifdef guard, "__ASM_STUB_" with no 
postfix.  So the second and later asm files #included in the same C file 
(often through standard headers like ioctl.h) yields no symbols.

--
There's a missing semicolon after the assignment to FNAME (so the assignment 
of STUBDEF on the next line doesn't see the value), and it helps to export 
variables before calling a subshell.

--- linux-2.6/scripts/Makefile.headersinst	2007-06-15 02:45:07.000000000 -0400
+++ linux/scripts/Makefile.headersinst	2007-06-26 08:54:13.000000000 -0400
@@ -108,8 +108,8 @@
 
 quiet_cmd_gen		  = GEN     $(patsubst $(INSTALL_HDR_PATH)/%,%,$@)
       cmd_gen		  = \
-FNAME=$(patsubst $(INSTALL_HDR_PATH)/$(_dst)/%,%,$@)			\
-STUBDEF=__ASM_STUB_`echo $$FNAME | tr a-z.- A-Z__`;			\
+export FNAME=$(patsubst $(INSTALL_HDR_PATH)/$(_dst)/%,%,$@);		\
+export STUBDEF=__ASM_STUB_`echo $$FNAME | tr a-z.- A-Z__`;		\
 (echo "/* File autogenerated by 'make headers_install' */" ;		\
 echo "\#ifndef $$STUBDEF" ;						\
 echo "\#define $$STUBDEF" ;						\

-- 
"One of my most productive days was throwing away 1000 lines of code."
  - Ken Thompson.