(Vlad Glagolev) Submitted a patch to fix command exec mode
under SPA message type validity test. Support for command exec mode was
also added to the test suite.
Enhanced the libfko decoding routine to include bounds checking on decrypted
SPA data. This includes verifying the number of fields within incoming SPA
data (colon separated) along with verifying string lengths of each field.
Added the 'const' qualifier to function prototype variables where possible.
In addition, reduced some functions to file-scope with 'static' where possible.
Also made a few minor changes to remove extra whitespace, and fixed a bug
in create_fwknoprc() to ensure the new fwknoprc filehandle is closed.