[libc] Fix malloc Block alignment issue on riscv32 (#117815)

Aligning blocks to max_align_t is neither necessary nor sufficient to
ensure that the usable_space() is so aligned. Instead, we make this an
invariant of Block and maintain it in init() and split().

This allows targets like riscv32 with small pointers and large
max_align_t to maintain the property that all available blocks are
aligned for malloc(). This change adjusts the tests to match and also
updates them closer to llvm-libc style.

0 files changed, 0 insertions, 0 deletions