pic32/olimex boards: Fix active state of button

Buttons for olimex_emz64 and olimex_hmz144 should be set
to active low in board configuration.

hw/bsp/pic32mz/boards/olimex_emz64/olimex_emz64.c

@@ -63,7 +63,7 @@ void led_init(void)
   // RB8 - LED
   // ANASELB RB8 not analog
   ANSELBCLR = TU_BIT(8);
-  // TRISH RH2 input
+  // TRISH RH2 output
   TRISBCLR = TU_BIT(8);
   // Initial value 0, LED off
   LATBCLR = TU_BIT(8);
@@ -128,7 +128,7 @@ void board_led_write(bool state)
 
 uint32_t board_button_read(void)
 {
-  return (PORTB >> 12) & 1;
+  return ((PORTB >> 12) & 1) == 0;
 }
 
 int board_uart_write(void const * buf, int len)

hw/bsp/pic32mz/boards/olimex_hmz144/olimex_hmz144.c

@@ -60,7 +60,7 @@ void led_init(void)
 {
   // RH2 - LED
   // ANASELH no analog function on RH2
-  // TRISH RH2 input
+  // TRISH RH2 output
   TRISHCLR = TU_BIT(2);
   // Initial value 0, LED off
   LATHCLR = TU_BIT(2);
@@ -126,7 +126,7 @@ void board_led_write(bool state)
 
 uint32_t board_button_read(void)
 {
-  return (PORTB >> 12) & 1;
+  return ((PORTB >> 12) & 1) == 0;
 }
 
 int board_uart_write(void const * buf, int len)