doc: Fix naming of SELinux

Reported-by: Tham Nguyen
Discussion: https://postgr.es/m/157851402876.29175.12977878383183540468@wrigleys.postgresql.org
Backpatch-through: 9.4

doc/src/sgml/ref/security_label.sgml

@@ -80,7 +80,7 @@ SECURITY LABEL [ FOR <replaceable class="parameter">provider</replaceable> ] ON
    label provider must interpret security labels; it merely provides a
    mechanism for storing them.  In practice, this facility is intended to allow
    integration with label-based mandatory access control (MAC) systems such as
-   <productname>SE-Linux</productname>.  Such systems make all access control decisions
+   <productname>SELinux</productname>.  Such systems make all access control decisions
    based on object labels, rather than traditional discretionary access control
    (DAC) concepts such as users and groups.
   </para>

src/test/modules/dummy_seclabel/README

-The dummy_seclabel module exists only to support regression
-testing of the SECURITY LABEL statement.  It is not intended
-to be used in production.
+The dummy_seclabel module exists only to support regression testing of
+the SECURITY LABEL statement.  It is not intended to be used in production.
 
 Rationale
 =========
 
-The SECURITY LABEL statement allows the user to assign security
-labels to database objects; however, security labels can only be assigned
-when specifically allowed by a loadable module, so this module is provided
-to allow proper regression testing.
+The SECURITY LABEL statement allows the user to assign security labels to
+database objects; however, security labels can only be assigned when
+specifically allowed by a loadable module, so this module is provided to
+allow proper regression testing.
 
 Security label providers intended to be used in production will typically be
-dependent on a platform-specific feature such as
-SE-Linux.  This module is platform-independent,
-and therefore better-suited to regression testing.
+dependent on a platform-specific feature such as SELinux.  This module is
+platform-independent, and therefore better-suited to regression testing.
 
 Usage
 =====