battery_statefs: fix a few build warnings

battery_statefs.c:95:8: warning: initializing 'char *' with an expression of type 'const char [38]' discards qualifiers [-Wincompatible-pointer-types-discards-qualifiers]
      {STATEFS_ROOT "Current", "current", NULL, 1e-6},        // from uA to A
       ^~~~~~~~~~~~~~~~~~~~~~

diff --git a/src/battery_statefs.c b/src/battery_statefs.c
index 4b9baf4..4f6a8c1 100644 (file)
--- a/src/battery_statefs.c
+++ b/src/battery_statefs.c
@@ -87,9 +87,9 @@ int battery_read_statefs(void) {
   }
 
   struct {
-    char *path;
-    char *type;
-    char *type_instance;
+    const char *path;
+    const char *type;
+    const char *type_instance;
     gauge_t factor;
   } metrics[] = {
       {STATEFS_ROOT "Current", "current", NULL, 1e-6},        // from uA to A