Fix memory errors

Several struct members were left uninitialized in some paths of the
code. Fix this by initializing all struct members to 0 in the affected
places.

Also fix an incorrectly sized malloc, where the size of a pointer
instead of the struct size was supplied to malloc.

src/impl/sysfs.c

@@ -5,12 +5,14 @@
 
 #include <stdio.h> //snprintf
 #include <stdlib.h> // malloc, free
+#include <string.h> // memset
 #include <dirent.h> // opendir, readdir
 
 static bool _impl_sysfs_init_leds(light_device_enumerator_t *enumerator)
 {
     // Create a new backlight device
     light_device_t *leds_device = malloc(sizeof(light_device_t));
+    memset(leds_device, 0, sizeof(light_device_t));
     snprintf(leds_device->name, sizeof(leds_device->name), "%s", "leds");
     
     // Add it to the enumerator 
@@ -63,6 +65,7 @@ static bool _impl_sysfs_init_backlight(light_device_enumerator_t *enumerator)
 {
     // Create a new backlight device
     light_device_t *backlight_device = malloc(sizeof(light_device_t));
+    memset(backlight_device, 0, sizeof(light_device_t));
     snprintf(backlight_device->name, sizeof(backlight_device->name), "%s", "backlight");
     
     // Add it to the enumerator 

src/light.c

@@ -435,7 +435,7 @@ light_device_enumerator_t * light_create_enumerator(light_context_t *ctx, char c
     }
     
     // Allocate the new enumerator
-    new_enumerators[ctx->num_enumerators] = malloc(sizeof(light_device_enumerator_t*));
+    new_enumerators[ctx->num_enumerators] = malloc(sizeof(light_device_enumerator_t));
     light_device_enumerator_t *returner = new_enumerators[ctx->num_enumerators];
     
     returner->devices = NULL;