x11rb: Update default cursor search path

[psychon]

In 1, xcb-util-cursor's default search path was changed. This change was done to bring it in line with libXcursor's behaviour. In that library, in 2, ~/.local/share/icons was added to the default search path.

Additionally, /usr/X11R6/lib/X11/icons was never part of libXcursor's search path. It only searched there if you set --prefix or --datadir suitably, but in that case /usr/share/icons would disappear from the search path. This path was thus removed from xcb-util-cursor in 1.

In this commit, I bring x11rb in sync with xcb-util-cursor again.

[psychon]

Dunno what to do best about the effects of rust-lang/rust#123168 :-(

error: unnecessary qualification
  --> x11rb-protocol/src/wrapper.rs:44:35
   |
44 |         let size = self.0.len() / core::mem::size_of::<T>();
   |                                   ^^^^^^^^^^^^^^^^^^^^^^^
   |
note: the lint level is defined here
  --> x11rb-protocol/src/lib.rs:49:5
   |
49 |     unused_qualifications,
   |     ^^^^^^^^^^^^^^^^^^^^^
help: remove the unnecessary path segments
   |
44 -         let size = self.0.len() / core::mem::size_of::<T>();
44 +         let size = self.0.len() / size_of::<T>();
   |

[notgull]

#931 was merged, so a rebase should fix the CI issues

[notgull]

Looks good to me!