Fix statement indent for c-ts-mode (bug#59686) (bug#60280)

Fix statement indent for c-ts-mode (bug#59686) (bug#60280)

Instead of trying to figure out the correct anchor, now we just count
the layers of {} blocks between the node and the root node.

* lisp/progmodes/c-ts-mode.el:
(c-ts-mode--indent-styles): Use new offset functions
c-ts-mode--close-bracket-offset and c-ts-mode--statement-offset.
(c-ts-mode--bracket-children-anchor): Remove function.
(c-ts-mode--top-level-label-matcher): New variable.
(c-ts-mode--statement-offset)
(c-ts-mode--close-bracket-offset): New offset functions.