Rollup merge of #119960 - cjgillot:inline-dg, r=WaffleLapkin

Inline 2 functions that appear in dep-graph profiles.

Those functions are small enough not to deserve a dedicated symbol.

compiler/rustc_index_macros/src/newtype.rs

@@ -263,6 +263,7 @@ impl #name {
             impl std::ops::Add<usize> for #name {
                 type Output = Self;
 
+                #[inline]
                 fn add(self, other: usize) -> Self {
                     Self::from_usize(self.index() + other)
                 }

compiler/rustc_query_system/src/dep_graph/serialized.rs

@@ -169,6 +169,7 @@ fn mask(self) -> u32 {
     }
 }
 
+#[inline]
 fn mask(bits: usize) -> usize {
     usize::MAX >> ((std::mem::size_of::<usize>() * 8) - bits)
 }