Fix build if the config is not updated

arch/arm/src/samv7/sam_gpio.c

@@ -78,6 +78,9 @@
 #    define SYSIO_BITS (MATRIX_CCFG_SYSIO_SYSIO4 | MATRIX_CCFG_SYSIO_SYSIO5)
 #  endif
 #endif
+#if !defined(SYSIO_BITS)
+#   define SYSIO_BITS 0
+#endif
 
 /****************************************************************************
  * Private Data

arch/arm/src/samv7/sam_start.c

@@ -58,6 +58,7 @@
 #include "sam_mpuinit.h"
 #include "sam_userspace.h"
 #include "sam_start.h"
+#include "sam_gpio.h"
 
 /****************************************************************************
  * Pre-processor Definitions