Remove a rendundant check for PidFile changes at runtime

This check is already performed regardless of whether the sandbox is active.

Fixes bug 21123; bugfix on commit 2ae47d3 in 0.2.5.4-alpha.

src/or/config.c

@@ -4522,7 +4522,6 @@ options_transition_allowed(const or_options_t *old,
     } while (0)
 
     SB_NOCHANGE_STR(Address);
-    SB_NOCHANGE_STR(PidFile);
     SB_NOCHANGE_STR(ServerDNSResolvConfFile);
     SB_NOCHANGE_STR(DirPortFrontPage);
     SB_NOCHANGE_STR(CookieAuthFile);