A few extra fsfunc symbols

Add fsfunc_Opt subreasons, fsfunc_DirIs subreasons.
Expand tabs on fsargs_IOCtl.
No code change, retagged as FileSwitch-2_84.

hdr/LowFSI

@@ -154,7 +154,7 @@ fsinfo_notforMultiFS    * :NOT: fsinfo_flushnotify      ; Anything other than fl
 fsextra_dirinformation  * 1 :SHL: 0     ; filing system supports fsfunc_DirIs
 fsextra_FSDoesCat       * 1 :SHL: 1     ; filing system does Cat rather than FileSwitch
 fsextra_FSDoesEx        * 1 :SHL: 2     ; filing system does Ex rather than FileSwitch
-fsextra_IOCtl		* 1 :SHL: 3	; filing system does IOCtls
+fsextra_IOCtl           * 1 :SHL: 3     ; filing system does IOCtls
 ; bits 4-31 unused (yet)
 
 ; Offsets from start of IFS information block in a IFS (MultiFS) module
@@ -171,6 +171,7 @@ IFS_file        #       4
 IFS_func        #       4
 IFS_size        *       @-IFS_info
 
+
 ; Reason codes passed to fscb^.File
 
 fsfile_Load          *  &FF
@@ -219,7 +220,8 @@ fsargs_EnsureSize       # 1     ; ARGS 6        7  All fs
 fsargs_WriteZeroes      # 1     ; internal      8  Only buffered fs
 fsargs_ReadLoadExec     # 1     ; internal      9  All fs
 fsargs_ImageStampIs     # 1     ; ARGS 8        10 Only
-fsargs_IOCtl		# 1	; ARGS 9	11
+fsargs_IOCtl            # 1     ; ARGS 9        11
+
 
 ; Reason codes passed to fscb^.Func
 
@@ -232,6 +234,8 @@ fsfunc_LCat                       # 1 ;4  FSC 7
 fsfunc_LEx                        # 1 ;5  FSC 8
 fsfunc_Info                       # 1 ;6  FSC 9
 fsfunc_Opt                        # 1 ;7  FSC 10
+fsfunc_Opt_Default                * 0
+fsfunc_Opt_Boot                   * 4
 fsfunc_Rename                     # 1 ;8  FSC 25
 fsfunc_Access                     # 1 ;9  FSC 24
 fsfunc_Bootup                     # 1 ;10 FSC 15
@@ -259,6 +263,10 @@ fsfunc_NameDisc                   # 1 ;31 for naming a disc
 fsfunc_StampImage                 # 1 ;32 for image stamping control
 fsfunc_ObjectAtOffset             # 1 ;33
 fsfunc_DirIs                      # 1 ;34 for NetFS (and others if they want)
+fsfunc_DirIs_CSD                  * 0
+fsfunc_DirIs_PSD                  * 1
+fsfunc_DirIs_URD                  * 2
+fsfunc_DirIs_Lib                  * 3
 fsfunc_ReadFreeSpace64            # 1 ;35 for reading the free space in 64 bit (FSC 55)
 fsfunc_DefectList64               # 1 ;36 for obtaining the image's defect list (two words per defect)
 fsfunc_AddDefect64                # 1 ;37 for adding a defect expressed in two words