ck: Merged FSCK+CK -> CK flag namespace

Unintentionally arriving at the infamous "fsck" name is a bit funny.

But it's probably something we don't want to conflict with if we can
help it, on the off chance we want a sort of lfs3_fsck function in the
future. (This is all hypothetical, but lfs3_fsck may expect an unmounted
filesystem, and have a much larger scope than lfs3_fs_ck. Though typing
this out now I'm realizing how confusing that might be...)

Since lfs3_file_ck and lfs3_fs_ck share a subset of flags, it's not
_entirely_ unreasonable for lfs3_file_ck and lfs3_fs_ck to share the
same namespace.

There's a risk of confusing users around what flags lfs3_file_ck
accepts, but we have asserts, and said flags (LFS3_CK_MKCONSISTENT,
LFS3_CK_LOOKAHEAD, etc) just don't really make sense in lfs3_file_ck:

  fs file
  y     LFS3_CK_MKCONSISTENT 0x00000800  Make the filesystem consistent
  y     LFS3_CK_LOOKAHEAD    0x00001000  Repopulate lookahead buffer
  y     LFS3_CK_LOOKGBMAP    0x00002000  Repopulate the gbmap
  y     LFS3_CK_PREERASE*    0x00004000  Pre-erase unused blocks
  y     LFS3_CK_COMPACTMETA  0x00008000  Compact metadata logs
  y  y  LFS3_CK_CKMETA       0x00010000  Check metadata checksums
  y  y  LFS3_CK_CKDATA       0x00020000  Check metadata + data checksums
  y  y  LFS3_CK_REPAIRMETA*  0x00040000  Repair data blocks
  y  y  LFS3_CK_REPAIRDATA*  0x00080000  Repair metadata + data blocks

  * Planned

Another option would be to document that lfs3_fs_ck accepts both
LFS3_CK_* _and_ LFS3_GC_* flags, but I worry that would be more
confusing. It would also lock us into supporting all LFs3_GC_* flags in
lfs3_fs_ck, which may not always be the case.

Though this is an argument for doing away with the whole
LFS3_M/F/CK/GC/I_* duplication... (tbh another reason for this is to
reduce the number of namespaces by at least one).

No code changes.

scripts/dbgflags.py

@@ -15,7 +15,6 @@ PREFIX_A       = ['--a', '--attr']      # Filter by LFS3_A_* flags
 PREFIX_F       = ['--f', '--format']    # Filter by LFS3_F_* flags
 PREFIX_M       = ['--m', '--mount']     # Filter by LFS3_M_* flags
 PREFIX_CK      = ['--ck']               # Filter by LFS3_CK_* flags
-PREFIX_FSCK    = ['--fsck']             # Filter by LFS3_FSCK_* flags
 PREFIX_GC      = ['--gc']               # Filter by LFS3_GC_* flags
 PREFIX_I       = ['--i', '--info']      # Filter by LFS3_I_* flags
 PREFIX_T       = ['--t', '--trv']       # Filter by LFS3_T_* flags
@@ -109,20 +108,14 @@ M_COMPACTMETA   = 0x00008000  # y-  Compact metadata logs
 M_CKMETA        = 0x00010000  # y-  Check metadata checksums
 M_CKDATA        = 0x00020000  # y-  Check metadata + data checksums
 
-# File check flags
+# File/filesystem check flags
+CK_MKCONSISTENT = 0x00000800  # --  Make the filesystem consistent
+CK_LOOKAHEAD    = 0x00001000  # --  Repopulate lookahead buffer
+CK_LOOKGBMAP    = 0x00002000  # --  Repopulate the gbmap
+CK_COMPACTMETA  = 0x00008000  # --  Compact metadata logs
 CK_CKMETA       = 0x00010000  # --  Check metadata checksums
 CK_CKDATA       = 0x00020000  # --  Check metadata + data checksums
 
-# Filesystem check flags
-FSCK_MKCONSISTENT \
-                = 0x00000800  # --  Make the filesystem consistent
-FSCK_LOOKAHEAD  = 0x00001000  # --  Repopulate lookahead buffer
-FSCK_LOOKGBMAP  = 0x00002000  # --  Repopulate the gbmap
-FSCK_COMPACTMETA \
-                = 0x00008000  # --  Compact metadata logs
-FSCK_CKMETA     = 0x00010000  # --  Check metadata checksums
-FSCK_CKDATA     = 0x00020000  # --  Check metadata + data checksums
-
 # GC flags
 GC_MKCONSISTENT = 0x00000800  # --  Make the filesystem consistent
 GC_LOOKAHEAD    = 0x00001000  # --  Repopulate lookahead buffer