docs/manual: svn downloads can be hash-checked

Since commit 89f5e989323a (support/download/svn: generate reproducible
svn archives), we've been able to generate reproducible archives, and
thus we have been able to verify the hashes for those archives.

However, the manual was not changed, and still falsely hinted that this
was not the cae.

Fix that.

Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
(cherry picked from commit 6898781f03140e301196a533953a202751be2f59)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

docs/manual/adding-packages-directory.txt

@@ -534,9 +534,9 @@ typically indicates that the +.hash+ file is wrong but the downloaded
 file is probably OK.
 
 Hashes are currently checked for files fetched from http/ftp servers,
-Git repositories, files copied using scp and local files. Hashes are
-not checked for other version control systems (such as Subversion,
-CVS, etc.) because Buildroot currently does not generate reproducible
+Git or subversion repositories, files copied using scp and local files.
+Hashes are not checked for other version control systems (such as CVS,
+mercurial) because Buildroot currently does not generate reproducible
 tarballs when source code is fetched from such version control
 systems.