beri loader: Replace getc/putc with beri_ prefixed versions

This matches a convention that we use, at least in ubldr, to prefix
getc/putc with a loader-specific prefix to avoid collisions. This was
encountered while trying to build the beri loader with MK_LOADER_LUA=yes.

No objection from:	brooks
Reported by:	emaste

stand/mips/beri/boot2/boot2.c

@@ -627,7 +627,7 @@ static int
 xputc(int c)
 {
     if (ioctrl & IO_KEYBOARD)
-	putc(c);
+	beri_putc(c);
 #if 0
     if (ioctrl & IO_SERIAL)
 	sio_putc(c);
@@ -642,7 +642,7 @@ xgetc(int fn)
 	return 0;
     for (;;) {
 	if (ioctrl & IO_KEYBOARD && keyhit(0))
-	    return fn ? 1 : getc();
+	    return fn ? 1 : beri_getc();
 #if 0
 	if (ioctrl & IO_SERIAL && sio_ischar())
 	    return fn ? 1 : sio_getc();

stand/mips/beri/common/altera_jtag_uart.c

@@ -159,7 +159,7 @@ keyhit(int seconds)
 }
 
 int
-getc(void)
+beri_getc(void)
 {
 
 	while (!(uart_readable()));
@@ -168,7 +168,7 @@ getc(void)
 }
 
 void
-putc(int ch)
+beri_putc(int ch)
 {
 
 	uart_data_write(ch);

stand/mips/beri/common/cons.h

@@ -33,8 +33,8 @@
 #ifndef _CONS_H_
 #define	_CONS_H_
 
-int	getc(void);
+int	beri_getc(void);
 int	keyhit(int);
-void	putc(int);
+void	beri_putc(int);
 
 #endif

stand/mips/beri/loader/beri_console.c

@@ -72,14 +72,14 @@ static void
 c_out(int c)
 {
 
-	putc(c);
+	beri_putc(c);
 }
 
 static int
 c_in(void)
 {
 
-	return (getc());
+	return (beri_getc());
 }
 
 static int