perf: Fix wrong name in comment for struct perf_cpu_context

Commit 0793a61d ("performance counters: core code") added the perf
subsystem (then called Performance Counters) to Linux, creating the struct
perf_cpu_context. The comment for the struct referred to it as a "struct
perf_counter_cpu_context".

Commit cdd6c482 ("perf: Do the big rename: Performance Counters ->
Performance Events") changed the comment to refer to a "struct
perf_event_cpu_context", which was still the wrong name for the struct.

Change the comment to say "struct perf_cpu_context".

CC: Thomas Gleixner <tglx@linutronix.de>
CC: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220127161759.53553-3-alexandru.elisei@arm.com

include/linux/perf_event.h

@@ -864,7 +864,7 @@ struct perf_event_context {
 #define PERF_NR_CONTEXTS	4
 
 /**
- * struct perf_event_cpu_context - per cpu event context structure
+ * struct perf_cpu_context - per cpu event context structure
  */
 struct perf_cpu_context {
 	struct perf_event_context	ctx;