Dropped LFSR_TYPE_UNKNOWN

Returning the actual on-disk file type is probably more useful for users
as this gives them more information.

I was originally concerned about collisions with future internal types,
LFS_TYPE_TRAVERSAL, etc, needed for internal opened-list tracking, but
it turns out we can avoid problems by starting internal types at 0x80,
since on-disk file types are only 7-bits.

Code changes:

           code          stack
  before: 33710           2592
  after:  33694 (-0.0%)   2592 (+0.0%)

lfs.c

@@ -9607,11 +9607,7 @@ static int lfsr_stat_(lfs_t *lfs, const lfsr_mdir_t *mdir,
         lfsr_tag_t tag, lfsr_data_t name,
         struct lfs_info *info) {
     // get file type from the tag
-    if (tag == LFSR_TAG_REG || tag == LFSR_TAG_DIR) {
-        info->type = lfsr_tag_subtype(tag);
-    } else {
-        info->type = LFS_TYPE_UNKNOWN;
-    }
+    info->type = lfsr_tag_subtype(tag);
 
     // read the file name
     LFS_ASSERT(lfsr_data_size(name) <= LFS_NAME_MAX);

lfs.h

@@ -114,7 +114,6 @@ enum lfs_error {
 // File types
 enum lfs_type {
     // file types
-    LFS_TYPE_UNKNOWN    = 0,
     LFS_TYPE_REG        = 1,
     LFS_TYPE_DIR        = 2,
 

tests/test_incompat.toml

@@ -359,11 +359,11 @@ code = '''
     // mount
     lfsr_mount(&lfs, CFG) => 0;
 
-    // our file should appear as unknown
+    // our file should appear as an unknown type
     struct lfs_info info;
     lfsr_stat(&lfs, "b", &info) => 0;
     assert(strcmp(info.name, "b") == 0);
-    assert(info.type == LFS_TYPE_UNKNOWN);
+    assert(info.type == 0x13);
     assert(info.size == 0);
 
     lfsr_dir_t dir;
@@ -382,7 +382,7 @@ code = '''
     assert(info.size == strlen("hi a!"));
     lfsr_dir_read(&lfs, &dir, &info) => 0;
     assert(strcmp(info.name, "b") == 0);
-    assert(info.type == LFS_TYPE_UNKNOWN);
+    assert(info.type == 0x13);
     assert(info.size == 0);
     lfsr_dir_read(&lfs, &dir, &info) => 0;
     assert(strcmp(info.name, "c") == 0);