main/openssh: move autoconf/automake to makedepends_build

these are actually build not host deps, and this fails on a bootstrap
otherwise as autoconf/automake are not cross-build for the host target.

fixes 9c0baee3

main/openssh/APKBUILD

@@ -12,9 +12,8 @@ arch="all"
 license="BSD"
 options="suid"
 depends="openssh-client openssh-sftp-server openssh-server"
+makedepends_build="autoconf automake"
 makedepends_host="
-	autoconf
-	automake
 	linux-headers
 	openssl1.1-compat-dev
 	zlib-dev