vendor.sh: print extract errors to /dev/null

the output isn't really super critical, because it pertains
to files that would just result in a coreboot build error
if they didn't extract, which would still allow me to know
if a given extract function failed.

however, the extract function shows a lot of error output
because it literally bruteforces various extract methods,
when dealing with vendor files.

mitigate this by just printing the errors to /dev/null. this
will prevent users from erroneously thinking that lbmk is
operating under error condition, when it isn't. we do sometimes
get questions about it on irc.

fewer questions on irc is better.

Signed-off-by: Leah Rowe <leah@libreboot.org>

include/vendor.sh

@@ -143,8 +143,9 @@ extract_intel_me()
 
 extract_archive()
 {
-	innoextract "$1" -d "$2" || python "$pfs_extract" "$1" -e || 7z x \
-	    "$1" -o"$2" || unar "$1" -o "$2" || unzip "$1" -d "$2" || return 1
+	innoextract "$1" -d "$2" 2>/dev/null || python "$pfs_extract" "$1" \
+	    -e 2>/dev/null || 7z x "$1" -o"$2" 2>/dev/null || unar "$1" -o \
+	    "$2" 2>/dev/null || unzip "$1" -d "$2" 2>/dev/null || return 1
 }
 
 extract_kbc1126ec()