GDB/testsuite: Expand Python integer parameter coverage across all types

Also verify PARAM_UINTEGER, PARAM_INTEGER, and PARAM_ZINTEGER parameter
types, in addition to PARAM_ZUINTEGER and PARAM_ZUINTEGER_UNLIMITED
already covered, and verify a choice of existing GDB parameters.  Add
verification for reading parameters via `<parameter>.value' in addition
to `gdb.parameter('<parameter>')' as this covers different code paths.

Approved-By: Simon Marchi <simon.marchi@polymtl.ca>
1 file changed