package/qoriq-rcw: rename from package/rcw

package/qoriq-rcw: rename from package/rcw

This is really only for QoriQ SoCs. Also the upstream package - despite
its base name of the git repository - is "qoriq-components/rcw". Thus
rename it to a more specify package name.

Note that there are other rcw implementations for other platforms, and
each implementation only applies to that specific platform; it hus does
not make sense that there are more than one rcw enabled at the same
time; so we keep using /usr/share/rcw as the install location; this also
help backward compatibility with existing post-build scripts.

Signed-off-by: Changming Huang <jerry.huang@nxp.com>
Cc: Michael Walle <michael@walle.cc>
[yann.morin.1998@free.fr:
  - rebase on master
  - incorporate changes by Michael
  - don't move to an 'nxp' sub-directory
  - reword the legacy entry; select the new package
  - expand commit log to explain why we keep installing in
    host/usr/share/rcw/ (thanks to Michael for prompting that)
]
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>