[nginx] Configure: fixed clang version detection (closes #1539).

[Ruslan Ermilov]

details:   http://hg.nginx.org/nginx/rev/ceab908790c4
branches:  
changeset: 7273:ceab908790c4
user:      Ruslan Ermilov <ru at nginx.com>
date:      Tue Apr 24 14:04:59 2018 +0300
description:
Configure: fixed clang version detection (closes #1539).

While 325b3042edd6 fixed it on MINIX, it broke it on systems
that output the word "version" on several lines with "cc -v".
The fix is to only consider "clang version" or "LLVM version"
as clang version, but this time only using sed(1).

diffstat:

 auto/cc/clang |  3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diffs (13 lines):

diff -r fa0e093b64d7 -r ceab908790c4 auto/cc/clang
--- a/auto/cc/clang	Tue May 08 19:35:56 2018 +0300
+++ b/auto/cc/clang	Tue Apr 24 14:04:59 2018 +0300
@@ -6,7 +6,8 @@
 
 
 NGX_CLANG_VER=`$CC -v 2>&1 | grep 'version' 2>&1 \
-                           | sed -e 's/^.* version \(.*\)/\1/'`
+                           | sed -n -e 's/^.*clang version \(.*\)/\1/p' \
+                                    -e 's/^.*LLVM version \(.*\)/\1/p'`
 
 echo " + clang version: $NGX_CLANG_VER"