efifb: Remove redundant efifb_setup_from_dmi stub

efifb is the only user of efifb_setup_from_dmi which is provided by
sysfb which is selected by efifb. That makes the stub redundant.
Signed-off-by: Michal Suchanek <msuchanek@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/7416c439d68e9e96068ea5c77e05c99c7df41750.1645822213.git.msuchanek@suse.de

include/linux/efi.h

@@ -1329,10 +1329,6 @@ static inline struct efi_mokvar_table_entry *efi_mokvar_entry_find(
 }
 #endif
 
-#ifdef CONFIG_SYSFB
 extern void efifb_setup_from_dmi(struct screen_info *si, const char *opt);
-#else
-static inline void efifb_setup_from_dmi(struct screen_info *si, const char *opt) { }
-#endif
 
 #endif /* _LINUX_EFI_H */