[expr.type.conv] Remove indirection of "specified type" (#4397)

The resulting type is always unqualified void, and the indirection is unnecessary.

Author: randomnetcat

source/expressions.tex

@@ -3269,7 +3269,7 @@
 Otherwise, if the type is \cv{}~\tcode{void}
 and the initializer is \tcode{()} or \tcode{\{\}}
 (after pack expansion, if any),
-the expression is a prvalue of the specified type
+the expression is a prvalue of type \tcode{void}
 that performs no initialization.
 Otherwise,
 the expression is a prvalue of the specified type