libmakepkg/lint_config: fix lint_variable actually running the PKGBUILD lint

Due to a copy-paste error when initially implementing this, it actually
uses a duplicate function name, usually resulting in lint_pkgbuild
overwriting the function definition.

Then the PKGBUILD lint gets run twice, one time before the PKGBUILD is
even sourced -- to potentially surprising results, like erroring out on
a pre-existing shell definition that doesn't match our expectations.

Seen in the wild with lint_config triggering an error for
'declare -x arch="foo"'

Signed-off-by: Eli Schwartz <eschwartz@archlinux.org>
Signed-off-by: Allan McRae <allan@archlinux.org>

scripts/libmakepkg/lint_config/variable.sh.in

@@ -25,10 +25,10 @@ LIBRARY=${LIBRARY:-'@libmakepkgdir@'}
 
 source "$LIBRARY/util/message.sh"
 
-lint_config_functions+=('lint_variable')
+lint_config_functions+=('lint_config_variables')
 
 
-lint_variable() {
+lint_config_variables() {
 	local array=(DLAGENTS VCSCLIENTS BUILDENV OPTIONS INTEGRITY_CHECK MAN_DIRS
 	             DOC_DIRS PURGE_TARGETS COMPRESSGZ COMPRESSBZ2 COMPRESSXZ
 	             COMPRESSLRZ COMPRESSLZO COMPRESSZ)