perf arm64: Fix mksyscalltbl, don't lose syscalls due to sort -nu

When using "sort -nu", arm64 syscalls were lost.  That is, the io_setup
syscall (number 0) and all but one (typically ftruncate; 64) of the
syscalls that are defined symbolically (like "#define __NR_ftruncate
__NR3264_ftruncate") at the point where "sort" is applied.

This creation-of-syscalls.c-scheme is, judging from comments,
copy-pasted from powerpc, and worked there because at the time, its
tools/arch/powerpc/include/uapi/asm/unistd.h had *literals*, like
"#define __NR_ftruncate 93".

With sort being numeric and the non-numeric key effectively evaluating
to 0, the sort option "-u" means these "duplicates" are removed.
There's no need to remove syscall lines with duplicate numbers for arm64
because there are none, so let's fix that by just losing the "-u".
Having the table numerically sorted on syscall-number for the rest of
the syscalls looks nice, so keep the "-n".

Reviewed-by: Leo Yan <leo.yan@linaro.org>
Signed-off-by: Hans-Peter Nilsson <hp@axis.com>
Tested-by: Leo Yan <leo.yan@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Garry <john.garry@huawei.com>
Cc: Kim Phillips <kim.phillips@arm.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org
Link: https://lore.kernel.org/r/20201228023941.E0DE2203B5@pchp3.se.axis.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/arch/arm64/entry/syscalls/mksyscalltbl

@@ -58,5 +58,5 @@ create_table()
 
 $gcc -E -dM -x c -I $incpath/include/uapi $input \
 	|sed -ne 's/^#define __NR_//p' \
-	|sort -t' ' -k2 -nu	       \
+	|sort -t' ' -k2 -n	       \
 	|create_table