Register simple function should not consider result type

[jinchengchenghh]

Bug description

When we register function with same input type and function name while overwrite is true, it should not consider resultType, but now, it cannot overwrite because integer variables is different in FunctionSignature.
#10467 (comment)
#10467 (comment)

System information

Velox System Info v0.0.2
Commit: 76c5795
CMake Version: 3.28.3
System: Linux-5.4.0-190-generic
Arch: x86_64
C++ Compiler: /usr/bin/c++
C++ Compiler Version: 9.4.0
C Compiler: /usr/bin/cc
C Compiler Version: 9.4.0
CMake Prefix Path: /usr/local;/usr;/;/usr/local/lib/python3.8/dist-packages/cmake/data;/usr/local;/usr/X11R6;/usr/pkg;/opt

[jinchengchenghh]

CC: @mbasmanova @kagamiori @kgpai @bikramSingh91