LONDON, April 4 : Chelsea are hoping that Saturday's 7-0 thrashing of lowly Port Vale in an FA Cup quarter-final draws a line under a dismal run of form and internal upheaval that has threatened to ruin the season of the big-spending Londoners.  The build-up to the tie had been dominated by Chelsea coach Liam Rosenior's announcement on Friday that club vice captain and record signing Enzo Fernandez would be suspended for two games after suggesting he might leave. Chelsea have been enveloped in