[Docs][Intrisics] Fix the name of llvm.memset.inline in the documentation (#180373)
LLVM intrinsic `llvm.memset.inline` indicates in its name the types of
the destination pointer and the size. There is no second pointer.
Moreover, the tests are already verifying that generated code uses
`@llvm.memset.inline.p0.i32` and `@llvm.memset.inline.p0.i64`. So make
the documentation reference these names as well.
Fixes: https://github.com/llvm/llvm-project/issues/163454