m68k/bvme6000: Include generic <linux/rtc.h>

The BVME6000 RTC driver doesn't use any MC146818-specific definitions,
hence include the generic <linux/rtc.h> instead of
<linux/mc146818rtc.h>.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

arch/m68k/bvme6000/rtc.c

@@ -15,7 +15,7 @@
 #include <linux/init.h>
 #include <linux/poll.h>
 #include <linux/module.h>
-#include <linux/mc146818rtc.h>	/* For struct rtc_time and ioctls, etc */
+#include <linux/rtc.h>	/* For struct rtc_time and ioctls, etc */
 #include <linux/bcd.h>
 #include <asm/bvme6000hw.h>