m68k: mvme: Remove overdue #warnings in RTC handling

The warnings were introduced when converting the MVME147 and MVME16x
RTC handling from gettod to hwclk.  Replace the #warning by a comment,
and return an error to inform the upper layer that writing to the RTC is
not yet supported.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20210907124511.2723414-1-geert@linux-m68k.org

arch/m68k/mvme147/config.c

@@ -171,7 +171,6 @@ static int bcd2int (unsigned char b)
 
 int mvme147_hwclk(int op, struct rtc_time *t)
 {
-#warning check me!
 	if (!op) {
 		m147_rtc->ctrl = RTC_READ;
 		t->tm_year = bcd2int (m147_rtc->bcd_year);
@@ -183,6 +182,9 @@ int mvme147_hwclk(int op, struct rtc_time *t)
 		m147_rtc->ctrl = 0;
 		if (t->tm_year < 70)
 			t->tm_year += 100;
+	} else {
+		/* FIXME Setting the time is not yet supported */
+		return -EOPNOTSUPP;
 	}
 	return 0;
 }

arch/m68k/mvme16x/config.c

@@ -436,7 +436,6 @@ int bcd2int (unsigned char b)
 
 int mvme16x_hwclk(int op, struct rtc_time *t)
 {
-#warning check me!
 	if (!op) {
 		rtc->ctrl = RTC_READ;
 		t->tm_year = bcd2int (rtc->bcd_year);
@@ -448,6 +447,9 @@ int mvme16x_hwclk(int op, struct rtc_time *t)
 		rtc->ctrl = 0;
 		if (t->tm_year < 70)
 			t->tm_year += 100;
+	} else {
+		/* FIXME Setting the time is not yet supported */
+		return -EOPNOTSUPP;
 	}
 	return 0;
 }