console: Squelch pre-console output in console functions

There are some locations in the code which anticipate printf() being called
before the console is ready by squelching printf() on gd->have_console.
Move this squelching into printf(), vprintf(), puts() and putc(). Also
make tstc() and getc() return 0 if console is not yet initialised

Signed-off-by: Graeme Russ <graeme.russ@gmail.com>
Tested-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/powerpc/cpu/mpc5xxx/i2c.c b/arch/powerpc/cpu/mpc5xxx/i2c.c
index 9fb330f..f9d293b 100644
--- a/arch/powerpc/cpu/mpc5xxx/i2c.c
+++ b/arch/powerpc/cpu/mpc5xxx/i2c.c
@@ -332,8 +332,7 @@
 		if (gd->flags & GD_FLG_RELOC) {
 			fdr = divider;
 		} else {
-			if (gd->have_console)
-				printf("%ld kHz, ", best_speed / 1000);
+			printf("%ld kHz, ", best_speed / 1000);
 			return divider;
 		}
 	}
@@ -374,34 +373,29 @@
 	xaddr[3] =  addr	& 0xFF;
 
 	if (wait_for_bb()) {
-		if (gd->have_console)
-			printf("i2c_read: bus is busy\n");
+		printf("i2c_read: bus is busy\n");
 		goto Done;
 	}
 
 	mpc_reg_out(&regs->mcr, I2C_STA, I2C_STA);
 	if (do_address(chip, 0)) {
-		if (gd->have_console)
-			printf("i2c_read: failed to address chip\n");
+		printf("i2c_read: failed to address chip\n");
 		goto Done;
 	}
 
 	if (send_bytes(chip, &xaddr[4-alen], alen)) {
-		if (gd->have_console)
-			printf("i2c_read: send_bytes failed\n");
+		printf("i2c_read: send_bytes failed\n");
 		goto Done;
 	}
 
 	mpc_reg_out(&regs->mcr, I2C_RSTA, I2C_RSTA);
 	if (do_address(chip, 1)) {
-		if (gd->have_console)
-			printf("i2c_read: failed to address chip\n");
+		printf("i2c_read: failed to address chip\n");
 		goto Done;
 	}
 
 	if (receive_bytes(chip, (char *)buf, len)) {
-		if (gd->have_console)
-			printf("i2c_read: receive_bytes failed\n");
+		printf("i2c_read: receive_bytes failed\n");
 		goto Done;
 	}
 
@@ -423,27 +417,23 @@
 	xaddr[3] =  addr	& 0xFF;
 
 	if (wait_for_bb()) {
-		if (gd->have_console)
-			printf("i2c_write: bus is busy\n");
+		printf("i2c_write: bus is busy\n");
 		goto Done;
 	}
 
 	mpc_reg_out(&regs->mcr, I2C_STA, I2C_STA);
 	if (do_address(chip, 0)) {
-		if (gd->have_console)
-			printf("i2c_write: failed to address chip\n");
+		printf("i2c_write: failed to address chip\n");
 		goto Done;
 	}
 
 	if (send_bytes(chip, &xaddr[4-alen], alen)) {
-		if (gd->have_console)
-			printf("i2c_write: send_bytes failed\n");
+		printf("i2c_write: send_bytes failed\n");
 		goto Done;
 	}
 
 	if (send_bytes(chip, (char *)buf, len)) {
-		if (gd->have_console)
-			printf("i2c_write: send_bytes failed\n");
+		printf("i2c_write: send_bytes failed\n");
 		goto Done;
 	}