selftests/timers: remove unused irqcount variable

When building with clang, via:

    make LLVM=1 -C tools/testing/selftest

...clang warns about an unused irqcount variable. clang is correct: the
variable is incremented and then ignored.

Fix this by deleting the irqcount variable.
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Acked-by: John Stultz <jstultz@google.com>
Reviewed-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

tools/testing/selftests/timers/rtcpie.c

@@ -29,7 +29,7 @@ static const char default_rtc[] = "/dev/rtc0";
 
 int main(int argc, char **argv)
 {
-	int i, fd, retval, irqcount = 0;
+	int i, fd, retval;
 	unsigned long tmp, data, old_pie_rate;
 	const char *rtc = default_rtc;
 	struct timeval start, end, diff;
@@ -120,7 +120,6 @@ int main(int argc, char **argv)
 
 			fprintf(stderr, " %d",i);
 			fflush(stderr);
-			irqcount++;
 		}
 
 		/* Disable periodic interrupts */