glib-2.0: use PN instead of glib-2.0 in PACKAGES and FILES

* otherwise notes like this are shown:
  NOTE: multiple providers are available for runtime glib-2.0-utils (glib-2.0-nativesdk, glib-2.0)
  NOTE: consider defining a PREFERRED_PROVIDER entry to match glib-2.0-utils

Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>