dumpcpp: Speculative fix for methods taking array type parameters.

QMetaMethod::methodSignature() produces for an invokable slot with
array type parameters (void foo(const char p1[10],int p2)):
foo(const char[10],int)
Split off the array specification and append it to the parameter name.

Task-number: QTBUG-46177
Change-Id: I58670570357472f6f5b7fcf0e841d3b7cb4189c8
Reviewed-by: Joerg Bornemann <joerg.bornemann@theqtcompany.com>