kbuild: sparse needs CF not CHECKFLAGS

Documentation/sparse.txt tells to use:

make C=2 CHECKFLAGS="-D__CHECK_ENDIAN__"

However, this still doesn't enable endian checks. The correct syntax is:

make C=2 CF="-D__CHECK_ENDIAN__"

This documentation bug was introduced by the following commit:

commit 1c7bafe7206d928eaccbcbd08d868733e0fb7054
Author: Robert P. J. Day <[e-mail]>
Date: Wed Sep 13 07:57:50 2006 -0400

kbuild: clarify "make C=" build option

Clarify the use of "make C=" in the top-level Makefile, and fix a
typo in the Documentation file.

Signed-off-by: Sam Ravnborg <[e-mail]>

This `typo' was not a typo, as `CF' had been introduced much earlier, by:

commit 7b49bb9aff8b14d15da58111d8908c877c0a525e
Author: [e-mail] <[e-mail]>
Date: Fri Sep 9 21:14:35 2005 +0100

[PATCH] kbuild: CF=<arguments> passes arguments to sparse

Allows to add to sparse arguments without mutilating makefiles - just
pass CF=<arguments> and they will be added to CHECKFLAGS.

Signed-off-by: Al Viro <[e-mail]>
Signed-off-by: Sam Ravnborg <[e-mail]>

Signed-off-by: Geert Uytterhoeven <[e-mail]>
Signed-off-by: Sam Ravnborg <[e-mail]>

Documentation/sparse.txt

···
 be recompiled or not.  The latter is a fast way to check the whole tree if you
 have already built it.
 
-The optional make variable CHECKFLAGS can be used to pass arguments to sparse.
-The build system passes -Wbitwise to sparse automatically.  To perform
-endianness checks, you may define __CHECK_ENDIAN__:
+The optional make variable CF can be used to pass arguments to sparse.  The
+build system passes -Wbitwise to sparse automatically.  To perform endianness
+checks, you may define __CHECK_ENDIAN__:
 
-        make C=2 CHECKFLAGS="-D__CHECK_ENDIAN__"
+        make C=2 CF="-D__CHECK_ENDIAN__"
 
 These checks are disabled by default as they generate a host of warnings.