path: Fixed ErrPath error.

include/ipfs/path/path.h

@@ -1,6 +1,7 @@
 #ifndef IPFS_PATH_H
    #define IPFS_PATH_H
 
+   #ifdef IPFS_PATH_C
       char *ErrPath[] = {
          NULL,
          // ErrBadPath is returned when a given path is incorrectly formatted
@@ -11,6 +12,9 @@
          NULL,
          "no link named %s under %s"
       };
+   #else
+      extern char **ErrPath;
+   #endif // IPFS_PATH_C
 
    enum {
        ErrBadPath = 1,

path/path.c

@@ -1,6 +1,7 @@
 #include <string.h>
 #include <stdlib.h>
 #include <ipfs/cid/cid.h>
+#define IPFS_PATH_C
 #include <ipfs/path/path.h>
 
 // FromCid safely converts a cid.Cid type to a Path type