Add some missing size macros.

These size macros are required to use the device specific functions
correctly and should therfore be exposed in the public api.

include/libdivecomputer/hw_frog.h

@@ -31,6 +31,9 @@
 extern "C" {
 #endif /* __cplusplus */
 
+#define HW_FROG_DISPLAY_SIZE    15
+#define HW_FROG_CUSTOMTEXT_SIZE 13
+
 dc_status_t
 hw_frog_device_open (dc_device_t **device, dc_context_t *context, const char *name);
 

include/libdivecomputer/hw_ostc.h

@@ -31,6 +31,9 @@
 extern "C" {
 #endif /* __cplusplus */
 
+#define HW_OSTC_MD2HASH_SIZE 18
+#define HW_OSTC_EEPROM_SIZE  256
+
 typedef enum hw_ostc_format_t {
 	HW_OSTC_FORMAT_RAW,
 	HW_OSTC_FORMAT_RGB16,

include/libdivecomputer/suunto_eon.h

@@ -30,6 +30,8 @@
 extern "C" {
 #endif /* __cplusplus */
 
+#define SUUNTO_EON_NAME_SIZE 20
+
 dc_status_t
 suunto_eon_device_open (dc_device_t **device, dc_context_t *context, const char *name);