perl: Add auto/XS/Typemap in perl-doc package

Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
conf: Remove unused ROOT_FLASH_SIZE variable from the config

This variable is set but never used in OE-core and meta-oe. It
was historically used for the Opie collection but seems to be
unused now.

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>