style-warning hides warnings when compiling write-string

[Roman Marynchak]

Surprisingly, the following garbage gets compiled with only a style warning:

* (defun cc() (write-string 1 2 3 4 5 6 7 8 9 10 11))
; in: LAMBDA NIL
; (WRITE-STRING 1 2 3 4 5 6 7 8 9 10 11)
;
; caught STYLE-WARNING:
; The function has an odd number of arguments in the keyword portion.
;
; compilation unit finished
; caught 1 STYLE-WARNING condition

However, the smaller garbage

* (defun k() (write-string 1 2))
; in: LAMBDA NIL
; (WRITE-STRING 1 2)
;
; caught WARNING:
; Asserted type STRING conflicts with derived type
; (VALUES (INTEGER 1 1) &OPTIONAL).
; See also:
; The SBCL Manual, Node "Handling of Types"
;
; compilation unit finished
; caught 1 WARNING condition

emits a full warning.

Also, the warning about too many arguments should be present.

Regards,
Roman