Upstream: style.

Signed-off-by: Piotr Sikora <piotrsikora@google.com>
diff --git a/src/http/ngx_http_upstream.c b/src/http/ngx_http_upstream.c
index 0fc5ab5..324c59b 100644
--- a/src/http/ngx_http_upstream.c
+++ b/src/http/ngx_http_upstream.c
@@ -2729,7 +2729,7 @@
     rev = c->read;
 
     ngx_log_debug0(NGX_LOG_DEBUG_HTTP, c->log, 0,
-                   "http upstream process body on memory");
+                   "http upstream process body in memory");
 
     if (rev->timedout) {
         ngx_connection_error(c, NGX_ETIMEDOUT, "upstream timed out");