[rtl/tlul] Fix typo in tlul_cmd_intg_gen.sv
[rtl/tlul] Fix typo in tlul_cmd_intg_gen.sv

Also, it is much better to use SV a ":" module_identifier with an
endmodule, since the compiler checks the identifier matches the module
name. This is also a good practice for other constructs, like tasks,
functions, interfaces, packages, classes, etc.

Signed-off-by: Guillermo Maturana <085716c7110d3f31793f7d964c2e5fd26da1c550@google.com>

lowRISC/opentitan,lowRISC/opentitan,lowRISC/opentitan,lowRISC/opentitan,lowRISC/opentitan,lowRISC/opentitan