developer.texi: Simplify "Regression tests section"

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

doc/developer.texi

@@ -422,22 +422,7 @@ separate patches.
 Before submitting a patch (or committing to the repository), you should at least
 test that you did not break anything.
 
-The regression tests build a synthetic video stream and a synthetic
-audio stream. These are then encoded and decoded with all codecs or
-formats. The CRC (or MD5) of each generated file is recorded in a
-result file. A 'diff' is launched to compare the reference results and
-the result file. The output is checked immediately after each test
-has run.
-
-The regression tests then go on to test the FFserver code with a
-limited set of streams. It is important that this step runs correctly
-as well.
-
-Run 'make test' to test all the codecs and formats. Commands like
-'make regtest-mpeg2' can be used to run a single test. By default,
-make will abort if any test fails. To run all tests regardless,
-use make -k. To get a more verbose output, use 'make V=1 test' or
-'make V=2 test'.
+Running 'make fate' accomplishes this, please see @file{doc/fate.txt} for details.
 
 [Of course, some patches may change the results of the regression tests. In
 this case, the reference results of the regression tests shall be modified