src/commonlib/lz4_wrapper: Correct inline asm for unaligned 64-bit copy

Rewrite inline assembly for ARMv7+ to correctly annotate inputs and
outputs.  On ARM GCC 6.1.1, this causes assembly output to change from
the incorrect

	@ r0 is allocated to hold dst and x0
	@ r1 is allocated to hold src and x1
	ldr r0, [r1]		@ clobbers dst!
	ldr r1, [r1, #4]
	str r0, [r0]
	str r1, [r0, #4]

to the correct

	@ r0 is allocated to hold dst
	@ r1 is allocated to hold src and x1
	@ r3 is allocated to hold x0
	ldr r3, [r1]
	ldr r1, [r1, #4]
	str r3, [r0]
	str r1, [r0, #4]

Also modify checkpatch.pl to ignore spaces before opening brackets when
used in inline assembly.

Change-Id: I255995f5e0a7b1a95375258755a93972c51d79b8
Signed-off-by: Benjamin Barenblat <bbaren@google.com>
Reviewed-on: https://review.coreboot.org/15216
Tested-by: build bot (Jenkins)
Reviewed-by: Julius Werner <jwerner@chromium.org>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>

util/lint/checkpatch.pl

@@ -3,6 +3,7 @@
 # (c) 2005, Joel Schopp <jschopp@austin.ibm.com> (the ugly bit)
 # (c) 2007,2008, Andy Whitcroft <apw@uk.ibm.com> (new conditions, test suite)
 # (c) 2008-2010 Andy Whitcroft <apw@canonical.com>
+# (c) 2016 Google Inc.
 # Licensed under the terms of the GNU GPL License version 2
 
 use strict;
@@ -3377,11 +3378,12 @@ sub process {
 #  1. with a type on the left -- int [] a;
 #  2. at the beginning of a line for slice initialisers -- [0...10] = 5,
 #  3. inside a curly brace -- = { [0...10] = 5 }
+#  4. in an extended asm instruction -- : [r0]"r"(r0)
 		while ($line =~ /(.*?\s)\[/g) {
 			my ($where, $prefix) = ($-[1], $1);
 			if ($prefix !~ /$Type\s+$/ &&
 			    ($where != 0 || $prefix !~ /^.\s+$/) &&
-			    $prefix !~ /[{,]\s+$/) {
+			    $prefix !~ /[{,:]\s+$/) {
 				if (ERROR("BRACKET_SPACE",
 					  "space prohibited before open square bracket '['\n" . $herecurr) &&
 				    $fix) {