[patch] fix not working KBUILD_EXTRA_SYMBOLS

[Peter Volkov]

If you even define KBUILD_EXTRA_SYMBOLS in Makefile it will not be
expanded into command line argument for modpost. Patch in a

Note: this bug was reported and kernel bugzilla:
http://bugzilla.kernel.org/show_bug.cgi?id=11567
and patch was included in -mm tree.

The patch was generated against 2.6.26 kernel but I suppose it should
work applies to the linux/kernel/git/torvalds/linux-2.6.git too.

-- 
Peter.
--- scripts/Makefile.modpost.orig	2008-09-14 13:34:16.000000000 +0400
+++ scripts/Makefile.modpost	2008-09-14 13:34:41.000000000 +0400
@@ -82,7 +82,7 @@
  $(if $(CONFIG_MODULE_SRCVERSION_ALL),-a,)       \
  $(if $(KBUILD_EXTMOD),-i,-o) $(kernelsymfile)   \
  $(if $(KBUILD_EXTMOD),-I $(modulesymfile))      \
- $(if $(KBUILD_EXTRA_SYMBOLS), $(patsubst %, -e %,$(EXTRA_SYMBOLS))) \
+ $(if $(KBUILD_EXTRA_SYMBOLS), $(patsubst %, -e %,$(KBUILD_EXTRA_SYMBOLS))) \
  $(if $(KBUILD_EXTMOD),-o $(modulesymfile))      \
  $(if $(CONFIG_DEBUG_SECTION_MISMATCH),,-S)      \
  $(if $(CONFIG_MARKERS),-K $(kernelmarkersfile)) \