Kernel/fs: Add symlink flag to sysfunc70 and update the English documentation (#656)

Used in 70.1 and 70.5 in the ext driver

Reviewed-on: #656
Reviewed-by: Ivan B <1+dunkaist@noreply.localhost>
Reviewed-by: Mikhail Frolov <mixa.frolov2003@gmail.com>
Co-authored-by: Matou1306 <mathieubotros@gmail.com>

kernel/trunk/docs/sysfuncs.txt

@@ -4148,6 +4148,7 @@ Structure of block of data for folder entry (BDFE):
       and after archiving this bit is cleared - it can be useful
       for automatically creating of backup-archives as at writing
       this bit is usually set
+    * bit 6 (mask 0x40): this is a symbolic link (currently only set by the ext driver).
   * +4: dword: encoding, equals to field +8 in the information structure
   * +8: 4*byte: time of file creation
   * +12 = +0xC: 4*byte: date of file creation

kernel/trunk/fs/ext.inc

@@ -212,6 +212,7 @@ DIR_DIRECTORY = 2
 DIR_SYMLINK = 7
 KOS_HIDDEN = 2
 KOS_DIRECTORY = 10h
+KOS_SYMLINK = 40h
 READ_ONLY = 1
 SYMLINK_MAX_DEPTH = 40
 FAST_SYMLINK_MAX_SIZE = 60
@@ -3392,6 +3393,11 @@ ext_ReadFolder:
         stosd
         mov     eax, [esi+INODE.fileSizeHigh]
         stosd
+        movzx   eax, [esi+INODE.accessMode]
+        and     eax, TYPE_MASK
+        cmp     eax, FLAG_SYMLINK
+        jne     @f
+        or      dword [edx], KOS_SYMLINK
 @@:
         mov     esi, [esp+12]
         movzx   ecx, [esi+DIRENTRY.nameLength]