Remove unused variable in wxDCImpl::CalculateEllipticPoints().

Closes #16433.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/branches/WX_3_0_BRANCH@77456 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
Avoid warning about unused variable in wxiOS build.

Define variable only used if wxOSX_USE_COCOA_OR_CARBON inside the check for it.

Closes #16435.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/branches/WX_3_0_BRANCH@77457 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
Avoid unnecessary assignment in wxOSX build.

Don't assign to the variable only to overwrite it with a new value.

Closes #16436.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/branches/WX_3_0_BRANCH@77458 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775