apparmor: fix build failure on sparc caused by undeclared signals

  In file included from security/apparmor/ipc.c:23:0:
  security/apparmor/include/sig_names.h:26:3: error: 'SIGSTKFLT' undeclared here (not in a function)
    [SIGSTKFLT] = 16, /* -, 16, - */
     ^
  security/apparmor/include/sig_names.h:26:3: error: array index in initializer not of integer type
  security/apparmor/include/sig_names.h:26:3: note: (near initialization for 'sig_map')
  security/apparmor/include/sig_names.h:51:3: error: 'SIGUNUSED' undeclared here (not in a function)
    [SIGUNUSED] = 34, /* -, 31, - */
     ^
  security/apparmor/include/sig_names.h:51:3: error: array index in initializer not of integer type
  security/apparmor/include/sig_names.h:51:3: note: (near initialization for 'sig_map')

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Fixes: c6bf1adaecaa ("apparmor: add the ability to mediate signals")
Signed-off-by: John Johansen <john.johansen@canonical.com>

security/apparmor/include/sig_names.h

@@ -23,7 +23,9 @@ static const int sig_map[MAXMAPPED_SIG] = {
 	[SIGPIPE] = 13,
 	[SIGALRM] = 14,
 	[SIGTERM] = 15,
+#ifdef SIGSTKFLT
 	[SIGSTKFLT] = 16,	/* -, 16, - */
+#endif
 	[SIGCHLD] = 17,		/* 20, 17, 18.  SIGCHLD -, -, 18 */
 	[SIGCONT] = 18,		/* 19, 18, 25 */
 	[SIGSTOP] = 19,		/* 17, 19, 23 */
@@ -47,7 +49,8 @@ static const int sig_map[MAXMAPPED_SIG] = {
 #if defined(SIGLOST) && SIGPWR != SIGLOST		/* sparc */
 	[SIGLOST] = 33,		/* unused on Linux */
 #endif
-#if defined(SIGLOST) && defined(SIGSYS) && SIGLOST != SIGSYS
+#if defined(SIGUNUSED) && \
+    defined(SIGLOST) && defined(SIGSYS) && SIGLOST != SIGSYS
 	[SIGUNUSED] = 34,	/* -, 31, - */
 #endif
 };