tools: do not include scripts/Kbuild.include

Since commit 57fd251c7896 ("kbuild: split cc-option and friends to
scripts/Makefile.compiler"), some kselftests fail to build.

The tools/ directory opted out Kbuild, and went in a different
direction. People copied scripts and Makefiles to the tools/ directory
to create their own build system.

tools/build/Build.include mimics scripts/Kbuild.include, but some
tool Makefiles include the Kbuild one to import a feature that is
missing in tools/build/Build.include:

 - Commit ec04aa3ae87b ("tools/thermal: tmon: use "-fstack-protector"
   only if supported") included scripts/Kbuild.include from
   tools/thermal/tmon/Makefile to import the cc-option macro.

 - Commit c2390f16fc5b ("selftests: kvm: fix for compilers that do
   not support -no-pie") included scripts/Kbuild.include from
   tools/testing/selftests/kvm/Makefile to import the try-run macro.

 - Commit 9cae4ace80ef ("selftests/bpf: do not ignore clang
   failures") included scripts/Kbuild.include from
   tools/testing/selftests/bpf/Makefile to import the .DELETE_ON_ERROR
   target.

 - Commit 0695f8bca93e ("selftests/powerpc: Handle Makefile for
   unrecognized option") included scripts/Kbuild.include from
   tools/testing/selftests/powerpc/pmu/ebb/Makefile to import the
   try-run macro.

Copy what they need into tools/build/Build.include, and make them
include it instead of scripts/Kbuild.include.

Link: https://lore.kernel.org/lkml/86dadf33-70f7-a5ac-cb8c-64966d2f45a1@linux.ibm.com/
Fixes: 57fd251c7896 ("kbuild: split cc-option and friends to scripts/Makefile.compiler")
Reported-by: Janosch Frank <frankja@linux.ibm.com>
Reported-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Yonghong Song <yhs@fb.com>
diff --git a/tools/build/Build.include b/tools/build/Build.include
index 585486e..2cf3b1b 100644
--- a/tools/build/Build.include
+++ b/tools/build/Build.include
@@ -100,3 +100,27 @@
 ## HOSTCC C flags
 
 host_c_flags = -Wp,-MD,$(depfile) -Wp,-MT,$@ $(KBUILD_HOSTCFLAGS) -D"BUILD_STR(s)=\#s" $(HOSTCFLAGS_$(basetarget).o) $(HOSTCFLAGS_$(obj))
+
+# output directory for tests below
+TMPOUT = .tmp_$$$$
+
+# try-run
+# Usage: option = $(call try-run, $(CC)...-o "$$TMP",option-ok,otherwise)
+# Exit code chooses option. "$$TMP" serves as a temporary file and is
+# automatically cleaned up.
+try-run = $(shell set -e;		\
+	TMP=$(TMPOUT)/tmp;		\
+	mkdir -p $(TMPOUT);		\
+	trap "rm -rf $(TMPOUT)" EXIT;	\
+	if ($(1)) >/dev/null 2>&1;	\
+	then echo "$(2)";		\
+	else echo "$(3)";		\
+	fi)
+
+# cc-option
+# Usage: cflags-y += $(call cc-option,-march=winchip-c6,-march=i586)
+cc-option = $(call try-run, \
+	$(CC) -Werror $(1) -c -x c /dev/null -o "$$TMP",$(1),$(2))
+
+# delete partially updated (i.e. corrupted) files on error
+.DELETE_ON_ERROR: