[openwrt/openwrt] bpf-headers: fix compilation with LLVM_IAS=1

[LEDE Commits]

hauke pushed a commit to openwrt/openwrt.git, branch openwrt-22.03:
https://git.openwrt.org/4a9eb94b5f1a1aeb2907952168605bcc9da1b4d3

commit 4a9eb94b5f1a1aeb2907952168605bcc9da1b4d3
Author: Hannu Nyman <hannu.nyman at iki.fi>
AuthorDate: Sun May 28 14:13:47 2023 +0300

    bpf-headers: fix compilation with LLVM_IAS=1
    
    Linux 5.10.178 includes backported commits that break the compilation
    of bpf-headers, as the compilation gets confused which assembler to use.
    Caused by Linux upstream commits just before the .178 tag:
    https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/log/?h=v5.10.178
    
    2023-04-20      kbuild: check CONFIG_AS_IS_LLVM instead of LLVM_IAS
    2023-04-20      kbuild: Switch to 'f' variants of integrated assembler flag
    2023-04-20      kbuild: check the minimum assembler version in Kconfig
    
    Explicitly use LLVM_IAS=1 to fix things.
    
    Fixes #12748
    
    Signed-off-by: Hannu Nyman <hannu.nyman at iki.fi>
---
 package/kernel/bpf-headers/Makefile | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package/kernel/bpf-headers/Makefile b/package/kernel/bpf-headers/Makefile
index 0c1a02a0a1..4de0968ec1 100644
--- a/package/kernel/bpf-headers/Makefile
+++ b/package/kernel/bpf-headers/Makefile
@@ -53,7 +53,7 @@ KERNEL_MAKE := \
 	$(MAKE) -C $(PKG_BUILD_DIR) \
 		ARCH=$(BPF_KARCH) \
 		CROSS_COMPILE=$(BPF_ARCH)-linux- \
-		LLVM=1 CC="$(CLANG)" LD="$(TARGET_CROSS)ld" \
+		LLVM=1 LLVM_IAS=1 CC="$(CLANG)" LD="$(TARGET_CROSS)ld" \
 		HOSTCC="$(HOSTCC)" \
 		HOSTCXX="$(HOSTCXX)" \
 		HOST_LOADLIBES="-L$(STAGING_DIR_HOST)/lib" \