(verilog-mode-map): Don't bind C-M-a,

(verilog-mode-map): Don't bind C-M-a,
C-M-e and C-M-h for emacs, they work by default.
(verilog-emacs-features): Remove.
(verilog-setup-dual-comments, verilog-populate-syntax-table):
Remove.  Move syntax table initialization ...
(verilog-mode-syntax-table): ... here.
(verilog-mode): Don't initialize the syntax table here.
(verilog-mark-defun): Only do something useful for XEmacs, emacs
does not need it.