fix from suffix to prefix

reference/constraints/File.rst

@@ -156,15 +156,15 @@ maxSize
 ~~~~~~~
 
 .. versionadded:: 2.6
-    The suffixes ``Ki`` and ``Mi`` were introduced in Symfony 2.6.
+    The prefixes ``Ki`` and ``Mi`` were introduced in Symfony 2.6.
 
 **type**: ``mixed``
 
 If set, the size of the underlying file must be below this file size in order
 to be valid. The size of the file can be given in one of the following formats:
 
 +--------+-----------+-----------------+------+
-| Suffix | Unit Name |      value      | e.g. |
+| Prefix | Unit Name |      value      | e.g. |
 +========+===========+=================+======+
 |        | byte      |          1 byte | 4096 |
 +--------+-----------+-----------------+------+
@@ -177,7 +177,7 @@ to be valid. The size of the file can be given in one of the following formats:
 | Mi     | mebibyte  | 1,048,576 bytes |  8Mi |
 +--------+-----------+-----------------+------+
 
-For more information about the difference between binary and SI suffixes,
+For more information about the difference between binary and SI prefixes,
 see `Wikipedia: Binary prefix`_.
 
 binaryFormat
@@ -188,12 +188,12 @@ binaryFormat
 
 **type**: ``boolean`` **default**: ``null``
 
-When ``true``, the sizes will be displayed in messages with binary suffixes
-(KiB, MiB). When ``false``, the sizes will be displayed with SI suffixes (kB,
-MB). When ``null``, then the binaryFormat will be guessed from the suffix
-defined in the ``maxSize`` option.
+When ``true``, the sizes will be displayed in messages with binary-prefixed
+units (KiB, MiB). When ``false``, the sizes will be displayed with SI-prefixed
+units (kB, MB). When ``null``, then the binaryFormat will be guessed from
+the value defined in the ``maxSize`` option.
 
-For more information about the difference between binary and SI suffixes,
+For more information about the difference between binary and SI prefixes,
 see `Wikipedia: Binary prefix`_.
 
 mimeTypes