csharp: Fix managed name when solving Get/SetType name clash

csharp: Fix managed name when solving Get/SetType name clash

Summary:
If you declare a property called "type", the generated getter method
would be called "GetType", clashing with "System.Object.GetType" method. The
current workaround for that is to straight-forwardly insert the respective
class/abstract's Eolian name into the function name (becoming, for example
"GetMy_ClassType"), sometimes getting inconsistent to not only other methods
but also with documentation (leading to XML errors, since a cref doc would
reference "GetMyClassType", which doesn't exists).

This patch fixes that by wrapping the Eolian name with the already existing
`managed_name` function.

Test Plan: Run ninja tests.

Reviewers: zmike, segfaultxavi

Reviewed By: segfaultxavi

Subscribers: cedric, #reviewers, #committers

Tags: #efl

Differential Revision: https://phab.enlightenment.org/D11331