fix(language_elements.md): edit referer

The old "extra" label was removed presuming a "standard label"
is sufficient here.

Signed-off-by: Norwid Behrnd <nbehrnd@yahoo.com>

Author: nbehrnd

source/learn/f95_features/language_elements.md

@@ -125,7 +125,7 @@ range(1_two_bytes)
 ```
 
 Also, in
-[`data` (initialization) statements](data_statement),
+[`data` (initialization) statements](data-statement),
 binary (`B`), octal (`O`) and hexadecimal (`Z`) constants
 may be used (often informally referred to as "BOZ constants"):
 
@@ -481,8 +481,6 @@ type(triplet), parameter      :: t = triplet((/0., 0., 0./))
 
 ### `data` statement
 
-(data_statement)=
-
 The `data` statement can be used for scalars and also for arrays and
 variables of derived type. It is also the only way to initialise just
 parts of such objects, as well as to initialise to binary, octal or