Fixed loop in ngx_writev_chain() and ngx_solaris_sendfilev_chain().

The "complete" flag wasn't cleared on loop iteration start, resulting in
broken behaviour if there were more than IOV_MAX buffers and first
iteration was fully completed (and hence the "complete" flag was set
to 1).
diff --git a/src/os/unix/ngx_solaris_sendfilev_chain.c b/src/os/unix/ngx_solaris_sendfilev_chain.c
index d68220d..64e59aa 100644
--- a/src/os/unix/ngx_solaris_sendfilev_chain.c
+++ b/src/os/unix/ngx_solaris_sendfilev_chain.c
@@ -74,7 +74,6 @@
 
 
     send = 0;
-    complete = 0;
 
     vec.elts = sfvs;
     vec.size = sizeof(sendfilevec_t);
@@ -87,6 +86,7 @@
         fprev = 0;
         sfv = NULL;
         eintr = 0;
+        complete = 0;
         sent = 0;
         prev_send = send;
 
diff --git a/src/os/unix/ngx_writev_chain.c b/src/os/unix/ngx_writev_chain.c
index 579fdec..a752b1f 100644
--- a/src/os/unix/ngx_writev_chain.c
+++ b/src/os/unix/ngx_writev_chain.c
@@ -54,7 +54,6 @@
     }
 
     send = 0;
-    complete = 0;
 
     vec.elts = iovs;
     vec.size = sizeof(struct iovec);
@@ -65,6 +64,7 @@
         prev = NULL;
         iov = NULL;
         eintr = 0;
+        complete = 0;
         prev_send = send;
 
         vec.nelts = 0;