fix typo

diff --git a/src/os/unix/ngx_process.c b/src/os/unix/ngx_process.c
index 5e88ef3..a1454b6 100644
--- a/src/os/unix/ngx_process.c
+++ b/src/os/unix/ngx_process.c

@@ -338,7 +338,7 @@
                 /*
                  * Ignore the signal in the new binary if its parent is
                  * not the init process, i.e. the old binary's process
-                 * is still running.  Or ingore the signal in the old binary's
+                 * is still running.  Or ignore the signal in the old binary's
                  * process if the new binary's process is already running.
                  */