nak: make it compile with clippy

nobody actually cares about fixing clippy warnings/errors inside NAK, so
drop the flags for now to make it at least compile.

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/27216>

src/nouveau/compiler/meson.build

@@ -34,14 +34,6 @@ _libbitview_rs = static_library(
   gnu_symbol_visibility : 'hidden',
   rust_abi : 'rust',
   rust_args : [
-    # we error on all clippy warnings unless they are disabled
-    '-Dclippy::all',
-    # we want to add asserts in control flow
-    '-Aclippy::assertions_on_constants',
-    # dunno, kind of looks nicier being explicit
-    '-Aclippy::redundant_field_names',
-    '-Aclippy::too_many_arguments',
-    '-Aclippy::type_complexity',
     '-Anon_snake_case',
   ],
 )
@@ -107,14 +99,6 @@ _libnak_rs = static_library(
   gnu_symbol_visibility : 'hidden',
   rust_abi : 'c',
   rust_args : [
-    # we error on all clippy warnings unless they are disabled
-    '-Dclippy::all',
-    # we want to add asserts in control flow
-    '-Aclippy::assertions_on_constants',
-    # dunno, kind of looks nicier being explicit
-    '-Aclippy::redundant_field_names',
-    '-Aclippy::too_many_arguments',
-    '-Aclippy::type_complexity',
     '-Anon_snake_case',
   ],
   link_with: [_libbitview_rs, libnak_bindings_gen, _libnak_ir_proc_rs],

src/nouveau/compiler/nak/assign_regs.rs

@@ -409,8 +409,6 @@ impl<'a> PinnedRegAllocator<'a> {
         align: u32,
         comps: u8,
     ) -> Option<u32> {
-        let align = align;
-
         let mut next_reg = start_reg;
         loop {
             let reg: u32 = self