kbuild: only one call for include/ in make headers_*

Move it to the top-level file to decide if we install/check
the generic headers or the arch specific headers.

This revealed a long standing bug where "make headers_check_all"
relied on the files in asm/ for the current architecture.
So make headers_check_all is now broken by this commit.

In addition:

o add a simpler way to detect if an arch support
  exporting header files.

o add 'set -e;' so we error out early if
  make headers_check_all fails.

o add sparc64 and cris to arch we do not process
  in make headers_*_all because:

    sparc64 - use sparc to export headers
    cris    - is know seriously broken

Includes suggestions from: David Woodhouse
<dwmw2@infradead.org>.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: David Woodhouse <dwmw2@infradead.org>

scripts/Makefile.headersinst

@@ -28,15 +28,6 @@ include $(kbuild-file)
 
 include scripts/Kbuild.include
 
-# If this is include/asm-$(ARCH) then override $(_dst) so that
-# we install to include/asm directly.
-# Unless $(BIASMDIR) is set, in which case we're probably doing
-# a 'headers_install_all' build and we should keep the -$(ARCH)
-# in the directory name.
-ifeq ($(obj),include/asm-$(ARCH)$(BIASMDIR))
-     _dst := include/asm
-endif
-
 install := $(INSTALL_HDR_PATH)/$(_dst)
 
 header-y	:= $(sort $(header-y) $(unifdef-y))