Added ngx_init_setproctitle() return code check.

The ngx_init_setproctitle() function, as used on systems without
setproctitle(3), may fail due to memory allocation errors, and
therefore its return code needs to be checked.

Reported by Markus Linnala.

src/os/unix/ngx_posix_init.c

diff --git a/src/os/unix/ngx_posix_init.c b/src/os/unix/ngx_posix_init.c
index 9a4de02..bf3a310 100644
--- a/src/os/unix/ngx_posix_init.c
+++ b/src/os/unix/ngx_posix_init.c
@@ -40,7 +40,9 @@
     }
 #endif
 
-    ngx_init_setproctitle(log);
+    if (ngx_init_setproctitle(log) != NGX_OK) {
+        return NGX_ERROR;
+    }
 
     ngx_pagesize = getpagesize();
     ngx_cacheline_size = NGX_CPU_CACHE_LINE;

src/os/unix/ngx_setproctitle.h

diff --git a/src/os/unix/ngx_setproctitle.h b/src/os/unix/ngx_setproctitle.h
index 2323408..c363662 100644
--- a/src/os/unix/ngx_setproctitle.h
+++ b/src/os/unix/ngx_setproctitle.h
@@ -13,7 +13,7 @@
 
 /* FreeBSD, NetBSD, OpenBSD */
 
-#define ngx_init_setproctitle(log)
+#define ngx_init_setproctitle(log) NGX_OK
 #define ngx_setproctitle(title)    setproctitle("%s", title)
 
 
@@ -39,7 +39,7 @@
 
 #else
 
-#define ngx_init_setproctitle(log)
+#define ngx_init_setproctitle(log) NGX_OK
 #define ngx_setproctitle(title)
 
 #endif /* OSes */