tools include UAPI: Synchronize linux/fcntl.h with the kernel sources

To pick up the changes in:

  6fd73538 ("mm/memfd: add F_SEAL_EXEC")

That doesn't add or change any perf tools functionality, only addresses
these build warnings:

  Warning: Kernel ABI header at 'tools/include/uapi/linux/fcntl.h' differs from latest version at 'include/uapi/linux/fcntl.h'
  diff -u tools/include/uapi/linux/fcntl.h include/uapi/linux/fcntl.h
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/include/uapi/linux/fcntl.h

@@ -43,6 +43,7 @@
 #define F_SEAL_GROW	0x0004	/* prevent file from growing */
 #define F_SEAL_WRITE	0x0008	/* prevent writes */
 #define F_SEAL_FUTURE_WRITE	0x0010  /* prevent future writes while mapped */
+#define F_SEAL_EXEC	0x0020  /* prevent chmod modifying exec bits */
 /* (1U << 31) is reserved for signed error codes */
 
 /*