Cleanup start logic in post.

Merge eoi_jmp_post() with check_restart_status() - it makes the logic
a little simpler to understand.
diff --git a/src/post.c b/src/post.c
index 4a87eca..00361d7 100644
--- a/src/post.c
+++ b/src/post.c
@@ -549,19 +549,6 @@
 }
 
 static void
-eoi_jmp_post()
-{
-    // XXX - this is supposed to jump without changing any memory -
-    // but the stack has been altered by the time the code gets here.
-    eoi_both_pics();
-    struct bregs br;
-    memset(&br, 0, sizeof(br));
-    br.cs = bda->jump_cs_ip >> 16;
-    br.ip = bda->jump_cs_ip;
-    call16(&br);
-}
-
-static void
 check_restart_status()
 {
     // Get and then clear CMOS shutdown status.
@@ -572,10 +559,19 @@
         // Normal post
         return;
 
-    if (status == 0x05)
-        eoi_jmp_post();
+    if (status != 0x05) {
+        BX_PANIC("Unimplemented shutdown status: %02x\n", status);
+        return;
+    }
 
-    BX_PANIC("Unimplemented shutdown status: %02x\n", status);
+    // XXX - this is supposed to jump without changing any memory -
+    // but the stack has been altered by the time the code gets here.
+    eoi_both_pics();
+    struct bregs br;
+    memset(&br, 0, sizeof(br));
+    br.cs = bda->jump_cs_ip >> 16;
+    br.ip = bda->jump_cs_ip;
+    call16(&br);
 }
 
 void VISIBLE