tools headers UAPI: Sync linux/prctl.h with the kernel sources

To pick the changes in:

  9e4ab6c8 ("arm64/sme: Implement vector length configuration prctl()s")

That don't result in any changes in tooling:

  $ tools/perf/trace/beauty/prctl_option.sh > before
  $ cp include/uapi/linux/prctl.h tools/include/uapi/linux/prctl.h
  $ tools/perf/trace/beauty/prctl_option.sh > after
  $ diff -u before after
  $

Just silences this perf tools build warning:

  Warning: Kernel ABI header at 'tools/include/uapi/linux/prctl.h' differs from latest version at 'include/uapi/linux/prctl.h'
  diff -u tools/include/uapi/linux/prctl.h include/uapi/linux/prctl.h

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mark Brown <broonie@kernel.org>
Link: http://lore.kernel.org/lkml/Yq81we+XFOqlBWyu@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/include/uapi/linux/prctl.h

@@ -272,6 +272,15 @@ struct prctl_mm_map {
 # define PR_SCHED_CORE_SCOPE_THREAD_GROUP	1
 # define PR_SCHED_CORE_SCOPE_PROCESS_GROUP	2
 
+/* arm64 Scalable Matrix Extension controls */
+/* Flag values must be in sync with SVE versions */
+#define PR_SME_SET_VL			63	/* set task vector length */
+# define PR_SME_SET_VL_ONEXEC		(1 << 18) /* defer effect until exec */
+#define PR_SME_GET_VL			64	/* get task vector length */
+/* Bits common to PR_SME_SET_VL and PR_SME_GET_VL */
+# define PR_SME_VL_LEN_MASK		0xffff
+# define PR_SME_VL_INHERIT		(1 << 17) /* inherit across exec */
+
 #define PR_SET_VMA		0x53564d41
 # define PR_SET_VMA_ANON_NAME		0