Fix button 2

I got the physical pin number and the logical Teensy one mixed up when
looking up what GPIO it is...

Change-Id: I34ff0ec8c2ab16d8098598d90c9e692ea72ae84e
diff --git a/motors/button_board.cc b/motors/button_board.cc
index 3fa3915..89ca864 100644
--- a/motors/button_board.cc
+++ b/motors/button_board.cc
@@ -72,7 +72,7 @@
 
     report[4] = (GPIO_BITBAND(GPIOD_PDIR, 5) << 0) |
                 (GPIO_BITBAND(GPIOD_PDIR, 6) << 1) |
-                (GPIO_BITBAND(GPIOD_PDIR, 16) << 2) |
+                (GPIO_BITBAND(GPIOB_PDIR, 0) << 2) |
                 (GPIO_BITBAND(GPIOB_PDIR, 1) << 3) |
                 (GPIO_BITBAND(GPIOA_PDIR, 14) << 4) |
                 (GPIO_BITBAND(GPIOE_PDIR, 26) << 5) |
@@ -232,7 +232,7 @@
   // BTN1
   PORTD_PCR6 = PORT_PCR_MUX(1);
   // BTN2
-  PORTD_PCR16 = PORT_PCR_MUX(1);
+  PORTB_PCR0 = PORT_PCR_MUX(1);
   // BTN3
   PORTB_PCR1 = PORT_PCR_MUX(1);
   // BTN4