x86/cacheinfo: Standardize _cpuid4_info_regs instance naming
The cacheinfo code frequently uses the output registers from CPUID leaf
0x4. Such registers are cached in 'struct _cpuid4_info_regs', augmented
with related information, and are then passed across functions.
The naming of these _cpuid4_info_regs instances is confusing at best.
Some instances are called "this_leaf", which is vague as "this" lacks
context and "leaf" is overly generic given that other CPUID leaves are
also processed within cacheinfo. Other _cpuid4_info_regs instances are
just called "base", adding further ambiguity.
Standardize on id4 for all instances.
Signed-off-by: Ahmed S. Darwish <darwi@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/r/20250324133324.23458-11-darwi@linutronix.de