perf augmented_raw_syscalls: Fix up comment

Cut'n'paste error, the second comment is about the syscalls that have as
its second arg a string.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-zo5s6rloy42u41acsf6q3pvi@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/examples/bpf/augmented_raw_syscalls.c

@@ -87,7 +87,7 @@ struct augmented_filename {
 #define SYS_SYMLINKAT          266
 #define SYS_MEMFD_CREATE       319
 
-/* syscalls where the first arg is a string */
+/* syscalls where the second arg is a string */
 
 #define SYS_PWRITE64            18
 #define SYS_EXECVE              59