bpftool: start builds from a clean build dir

Nothing cleans ${B} between rebuilds and the kernel makefiles cache
their feature detection results there, so a sysroot-only change (say
binutils leaving DEPENDS) skips the relink and packages a stale
binary that still links libbfd.

Signed-off-by: mark.yang <mark.yang@lge.com>
Signed-off-by: Khem Raj <khem.raj@oss.qualcomm.com>

meta-oe/recipes-kernel/bpftool/bpftool.bb

@@ -26,6 +26,8 @@ SECURITY_CFLAGS = ""
 
 do_configure[depends] += "virtual/kernel:do_shared_workdir"
 
+do_configure[cleandirs] = "${B}"
+
 COMPATIBLE_HOST = "(x86_64|aarch64|riscv64).*-linux"
 
 do_compile() {