Add ETPRIsize_t support to ExecuTorch for Xtensa (#7895)

Summary:

topic: not user facing

Our Xtensa G3's toolchain, which is as recent as RJ-2024.3 release doesn't have %zu format specifier support. Since we only have the precompiled libc.a provided from cadence -- it seems from the disassembly that only the following are supported

%c: character
%s: string
%d: decimal integer
%i: decimal integer (same as %d)
%u: unsigned decimal integer
%x: hexadecimal integer
%X: uppercase hexadecimal integer
%p: pointer

which is consistent with what I've seen come-out from ET_LOG prints that pass through the vsnprintf specifier

Haven't heard of a 64-bit Xtensa DSP, so I think this 'lu' specifier mapping should work for all Xtensa toolchains regardless of vsnprintf implementation.

This diff also updates a couple of places where I most commonly see the mishandled %zu specifier. If the changes are okay, I can more widely update print statements in ExecuTorch. It would touch a lot of files, some of which would never be compiled for Xtensa.

Differential Revision: D68131252

Author: cmt0

runtime/core/hierarchical_allocator.h

@@ -62,14 +62,16 @@ class HierarchicalAllocator final {
     ET_CHECK_OR_RETURN_ERROR(
         memory_id < buffers_.size(),
         InvalidArgument,
-        "id %" PRIu32 " >= %zu",
+        "id %" PRIu32 " >= %" ET_PRIsize_t,
         memory_id,
         buffers_.size());
     Span<uint8_t> buffer = buffers_[memory_id];
     ET_CHECK_OR_RETURN_ERROR(
         offset_bytes + size_bytes <= buffer.size(),
         MemoryAllocationFailed,
-        "offset_bytes (%zu) + size_bytes (%zu) >= allocator size (%zu) "
+        "offset_bytes (%" ET_PRIsize_t ") + size_bytes (%" ET_PRIsize_t
+        ") >= allocator size (%" ET_PRIsize_t
+        ") "
         "for memory_id %" PRIu32,
         offset_bytes,
         size_bytes,