Fix GPIO setup during BMC initialization

This fixes LPC clock start failures from the
clock buffer GPIO not being set to output mode.

kestrel/src/kestrel.c

@@ -447,9 +447,13 @@ static void display_post_code(uint16_t post_code)
 
 static void gpio_init(void)
 {
+    // Disable LPC clock buffer
+    gpio1_out_write(gpio1_out_read() & ~(0x01 << 12));
+    gpio1_oe_write(gpio1_oe_read() | (0x01 << 12));
+
     // Set up discrete LED bank
     set_led_bank_display(0x00);
-    gpio1_oe_write(0xf);
+    gpio1_oe_write(gpio1_oe_read() | 0xf);
 
     // Set up alphanumeric display / power LED
     gpio2_out_write((' ' << 24) | (' ' << 16) | (' ' << 8) | ' ');