[meta] Add more pub(crate) definitions.

cranelift/codegen/meta/src/isa/x86/registers.rs

@@ -1,6 +1,6 @@
 use crate::cdsl::regs::{IsaRegs, IsaRegsBuilder, RegBankBuilder, RegClassBuilder};
 
-pub fn define() -> IsaRegs {
+pub(crate) fn define() -> IsaRegs {
     let mut regs = IsaRegsBuilder::new();
 
     let builder = RegBankBuilder::new("IntRegs", "r")

cranelift/codegen/meta/src/isa/x86/settings.rs

@@ -1,6 +1,6 @@
 use crate::cdsl::settings::{PredicateNode, SettingGroup, SettingGroupBuilder};
 
-pub fn define(shared: &SettingGroup) -> SettingGroup {
+pub(crate) fn define(shared: &SettingGroup) -> SettingGroup {
     let mut settings = SettingGroupBuilder::new("x86");
 
     // CPUID.01H:ECX