rust: alloc: rename KernelAllocator to Kmalloc

Subsequent patches implement `Vmalloc` and `KVmalloc` allocators, hence
align `KernelAllocator` to this naming scheme.

Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20241004154149.93856-4-dakr@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Author: Danilo Krummrich

rust/kernel/alloc/allocator.rs

@@ -6,7 +6,7 @@ use super::{flags::*, Flags};
 use core::alloc::{GlobalAlloc, Layout};
 use core::ptr;
 
-struct KernelAllocator;
+struct Kmalloc;
 
 /// Returns a proper size to alloc a new object aligned to `new_layout`'s alignment.
 fn aligned_size(new_layout: Layout) -> usize {
@@ -37,7 +37,7 @@ pub(crate) unsafe fn krealloc_aligned(ptr: *mut u8, new_layout: Layout, flags: F
 }
 
 // SAFETY: TODO.
-unsafe impl GlobalAlloc for KernelAllocator {
+unsafe impl GlobalAlloc for Kmalloc {
     unsafe fn alloc(&self, layout: Layout) -> *mut u8 {
         // SAFETY: `ptr::null_mut()` is null and `layout` has a non-zero size by the function safety
         // requirement.
@@ -74,7 +74,7 @@ unsafe impl GlobalAlloc for KernelAllocator {
 }
 
 #[global_allocator]
-static ALLOCATOR: KernelAllocator = KernelAllocator;
+static ALLOCATOR: Kmalloc = Kmalloc;
 
 // See <https://github.com/rust-lang/rust/pull/86844>.
 #[no_mangle]