tools/build: Fix 'unused variable' warning in the bpf() feature check

I deleted slightly too much when removing the run-time check.

debian/changelog

@@ -6,6 +6,7 @@ linux-tools (4.5~rc5-1~exp4) UNRELEASED; urgency=medium
   * hyperv-daemons: Fix rule redefinition that 'make' warns about
   * debian/control: Build-Depend on dh-python, as dh_python2 warns we should
   * lockdep: Add '+' prefix to make invocation, so it can be parallelised
+  * tools/build: Fix 'unused variable' warning in the bpf() feature check
 
  -- Ben Hutchings <ben@decadent.org.uk>  Mon, 22 Feb 2016 23:21:57 +0000
 

debian/patches/tools-build-remove-bpf-run-time-check-at-build-time.patch

@@ -10,11 +10,10 @@ Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
 ---
 --- a/tools/build/feature/test-bpf.c
 +++ b/tools/build/feature/test-bpf.c
-@@ -27,10 +27,5 @@ int main(void)
- 	attr.log_level = 0;
+@@ -28,9 +28,5 @@ int main(void)
  	attr.kern_version = 0;
  
--	attr = attr;
+ 	attr = attr;
 -	/*
 -	 * Test existence of __NR_bpf and BPF_PROG_LOAD.
 -	 * This call should fail if we run the testcase.