redundant redeclaration in 0.94

[Ali Abdallah]

Hi,

Of course totally harmless, but there is 3 redundant redeclaration in 
Polkit 0.94 which cause compilation error when compiling with -Werror 
and -Wredundant-decls options sometimes we use.

polkit_implicit_authorization_get_type in polkitimplicitauthorization.h 
and polkitenumtypes.h

polkit_error_get_type in polkiterror.h and polkitenumtypes.h

polkit_check_authorization_flags_get_type in 
polkitcheckauthorizationflags.h and polkitenumtypes.h

It will be nice if those will be fixed.

Cheers.