Remove the legacy_test_helper and legacy_setup wrappers

These wrappers went into place when the default type for our unit
test functions changed from "void fn(void)" to "void fn(void *arg)".

To generate this patch, I did the same hokey-pokey as before with
replacing all operators used as macro arguments, then I ran a
coccinelle script, then I ran perl script to fix up everything that
used legacy_test_helper, then I manually removed the
legacy_test_helper functions, then I ran a final perl script to put
the operators back how they were.

==============================
 #!/usr/bin/perl -w -i -p

s/==,/_X_EQ_,/g;
s/!=,/_X_NE_,/g;
s/<,/_X_LT_,/g;
s/>,/_X_GT_,/g;
s/>=,/_X_GEQ_,/g;
s/<=,/_X_LEQ_,/g;

--------------------

@@
identifier func =~ "test_.*$";
statement S, S2;
@@
 static void func (
-void
+void *arg
 )
 {
 ... when != S2
+(void) arg;
 S
 ...
 }

--------------------
 #!/usr/bin/perl -w -i -p

s/, *legacy_test_helper, *([^,]+), *\&legacy_setup, *([^\}]+) *}/, $2, $1, NULL, NULL }/g;

--------------------
 #!/usr/bin/perl -w -i -p

s/_X_NEQ_/!=/g;
s/_X_NE_/!=/g;
s/_X_EQ_/==/g;
s/_X_GT_/>/g;
s/_X_LT_/</g;
s/_X_GEQ_/>=/g;
s/_X_LEQ_/<=/g;

--------------------