kernel/linux: fix using custom location

Currently, extract and patch are skipped as thus:
- using a custom directory of pre-installed headers
- a correctly named directory already exists

Otherwise, extract and patch are done.

The current second condition is wrong, because it allows the following
sequence to happen:
- a non-custom kernel is used
- a previous build only partially extracted the non-custom sources
- that p[revious build broke during extraction (eg. incomplete tarball...)
- a subsequent build will find a properly named directory, and will
thus skip extract and patch, which is wrong

Fix that by following the conditions in this table:

Type | Extract | Patch
----------------------+---------+-------
Pre-installed headers | N | N
custom directory | N | N
custom tarball | Y | N
mainstream tarball | Y | Y

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Cc: David Holsgrove <david.holsgrove@xilinx.com>

diff -ur gcc-4.4.1-orig/libjava/Makefile.in gcc-4.4.1/libjava/Makefile.in

--- gcc-4.4.1-orig/libjava/Makefile.in	2009-08-04 04:12:27.000000000 -0700

+++ gcc-4.4.1/libjava/Makefile.in	2009-09-23 22:03:15.750951483 -0700

@@ -8874,6 +8874,9 @@

 ecjx$(EXEEXT): $(ecjx_OBJECTS) $(ecjx_DEPENDENCIES) 

 	@rm -f ecjx$(EXEEXT)

 	$(ecjx_LINK) $(ecjx_LDFLAGS) $(ecjx_OBJECTS) $(ecjx_LDADD) $(LIBS)

+ecjx.$(OBJEXT): $(ecjx_SOURCES)

+	@rm -f ecjx.$(OBJEXT)

+	$(CC_FOR_BUILD) $(BUILD_CFLAGS) -c -o $@ $<

 gappletviewer$(EXEEXT): $(gappletviewer_OBJECTS) $(gappletviewer_DEPENDENCIES) 

 	@rm -f gappletviewer$(EXEEXT)

 	$(gappletviewer_LINK) $(gappletviewer_LDFLAGS) $(gappletviewer_OBJECTS) $(gappletviewer_LDADD) $(LIBS)