tools/bpf: Rename 'struct event' to avoid naming conflict

On ppc64le, trying to build bpf seltests throws the below warning:
  In file included from runqslower.bpf.c:5:
  ./runqslower.h:7:8: error: redefinition of 'event'
  struct event {
	 ^
  /home/naveen/linux/tools/testing/selftests/bpf/tools/build/runqslower/vmlinux.h:156602:8:
  note: previous definition is here
  struct event {
	 ^

This happens since 'struct event' is defined in
drivers/net/ethernet/alteon/acenic.h . Rename the one in runqslower to a
more appropriate 'runq_event' to avoid the naming conflict.

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/c13cb3767d26257ca4387b8296b632b433a58db6.1641468127.git.naveen.n.rao@linux.vnet.ibm.com

Author: rnav

tools/bpf/runqslower/runqslower.bpf.c

@@ -68,7 +68,7 @@ int handle__sched_switch(u64 *ctx)
 	 */
 	struct task_struct *prev = (struct task_struct *)ctx[1];
 	struct task_struct *next = (struct task_struct *)ctx[2];
-	struct event event = {};
+	struct runq_event event = {};
 	u64 *tsp, delta_us;
 	long state;
 	u32 pid;

tools/bpf/runqslower/runqslower.c

@@ -100,7 +100,7 @@ static int bump_memlock_rlimit(void)
 
 void handle_event(void *ctx, int cpu, void *data, __u32 data_sz)
 {
-	const struct event *e = data;
+	const struct runq_event *e = data;
 	struct tm *tm;
 	char ts[32];
 	time_t t;

tools/bpf/runqslower/runqslower.h

@@ -4,7 +4,7 @@
 
 #define TASK_COMM_LEN 16
 
-struct event {
+struct runq_event {
 	char task[TASK_COMM_LEN];
 	__u64 delta_us;
 	pid_t pid;