x86/cpu: Use max() for CPUID leaf 0x2 TLB descriptors parsing

The conditional statement "if (x < y) { x = y; }" appears 22 times at
the Intel leaf 0x2 descriptors parsing logic.

Replace each of such instances with a max() expression to simplify
the code.

Signed-off-by: Ahmed S. Darwish <darwi@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20250304085152.51092-7-darwi@linutronix.de