If a depends (makedepends, checkdepends, optdepends, conflicts,
provides, replaces, license, groups, source) line appears in a package
section, it replaces the corresponding array from the pkgbase section.
If there is a single "depends = " line in the package section, the
depends array of that package is considered empty.

This partly reverts the behavior introduced in commit 137a9ae (Fix
parsing of array overrides, 2014-05-03).

Signed-off-by: Lukas Fleischer <archlinux@cryptocrack.de>