Add missing sha224 sums in man page and linting

Signed-off-by: morganamilo <morganamilo@gmail.com>
Signed-off-by: Allan McRae <allan@archlinux.org>

doc/PKGBUILD.5.asciidoc

@@ -154,7 +154,7 @@ contain whitespace characters.
 	be skipped. To easily generate md5sums, run ``makepkg -g >> PKGBUILD''.
 	If desired, move the md5sums line to an appropriate location.
 
-*sha1sums, sha256sums, sha384sums, sha512sums (arrays)*::
+*sha1sums, sha224sums, sha256sums, sha384sums, sha512sums (arrays)*::
 	Alternative integrity checks that makepkg supports; these all behave
 	similar to the md5sums option described above. To enable use and generation
 	of these checksums, be sure to set up the `INTEGRITY_CHECK` option in

scripts/libmakepkg/lint_pkgbuild/variable.sh.in

@@ -34,7 +34,8 @@ lint_variable() {
 	local array=(arch backup checkdepends groups license noextract options
 	             validpgpkeys)
 	local arch_array=(conflicts depends makedepends md5sums optdepends provides
-	                  replaces sha1sums sha256sums sha384sums sha512sums source)
+	                  replaces sha1sums sha224sums sha256sums sha384sums sha512sums
+			  source)
 	local string=(changelog epoch install pkgdesc pkgrel pkgver url)
 
 	local i a v pkg keys out bad ret=0