list->c32vector and list->c64vector should accept complex numbers

[Tobias Brandt]

I expected this to work:

scheme@(guile-user)> (use-modules (srfi srfi-4 gnu))
scheme@(guile-user)> (list->c64vector '(1.0+1.0i))
srfi/srfi-4/gnu.scm:92:2: In procedure bytevector-c64-native-set!:
srfi/srfi-4/gnu.scm:92:2: Wrong type (expecting real number): 1.0+1.0i