Remove unused variables

MSP-9228
Remove unused block

MSP-9228
Metasploit::Framework::Framework::Pathnames#data

MSP-9228

The framework-specific root can also have a data directory.
Msf::DBManager#import_ip360_aspl_xml compatibility

MSP-9228

Spec and swap to framework.pathnames.
Fully-qualified DBImportError

MSP-9228

Needs to be Msf::DBImportError because Msf is no longer in the lexical
scope after the Msf::DBManager break-up.