x86/alternatives: Simplify and clean up patch_cmp()

x86/alternatives: Simplify and clean up patch_cmp()

- No need to cast over to 'struct smp_text_poke_loc *', void * is just fine
  for a binary search,

- Use the canonical (a, b) input parameter nomenclature of cmp_func_t
  functions and rename the input parameters from (tp, elt) to
  (tpl_a, tpl_b).

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-44-mingo@kernel.org