crossgcc: Update to clang 4.0

Drop Edward's cfe patch because it has been implemented by
upstream clang differently. Instead of

 $ clang --print-librt-file-name

the right way to get ahold of the compiler-rt builtin library is

 $ clang -rtlib=compiler-rt --print-libgcc-file-name

Change-Id: I8aac5256da5bfb6f7bebeff0959f16b53867c581
Signed-off-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Reviewed-on: https://review.coreboot.org/20274
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Patrick Georgi <pgeorgi@google.com>

util/crossgcc/buildgcc

@@ -47,7 +47,7 @@ IASL_VERSION=20161222
 PYTHON_VERSION=3.5.1
 EXPAT_VERSION=2.1.1
 # CLANG version number
-CLANG_VERSION=3.9.1
+CLANG_VERSION=4.0.0
 MAKE_VERSION=4.2.1
 CMAKE_VERSION=3.9.0-rc3
 
@@ -868,8 +868,8 @@ case "$PACKAGE" in
 		;;
 	CLANG|clang)
 		NAME=clang
-		PACKAGES="LLVM CFE CRT CTE"
-		CMAKE=$(searchtool cmake "cmake") || exit $?
+		PACKAGES="CMAKE LLVM CFE CRT CTE"
+		CMAKE=${DESTDIR}${TARGETDIR}/bin/cmake
 		;;
 	IASL|iasl)
 		NAME="IASL ACPI compiler"