Revert _Pragma operator

Revert "Add support for C11-style _Pragma operator on processpre".
Revert "Add unit test for the _Pragma operator".

This reverts commits 31fcb331c7 and e261ac2121.

This should rather be the job of the preprocessor, which should generate #pragma lines. gcc does that.

unit_tests/coverage.suite/pragma-operator.lsl

@@ -1,14 +0,0 @@
-_Pragma("OPT inline")
-
-string f(integer x) inline
-{
-    return "ok";
-}
-
-default
-{
-    state_entry()
-    {
-        llOwnerSay(f(5));
-    }
-}

unit_tests/coverage.suite/pragma-operator.out

@@ -1,18 +0,0 @@
-default
-{
-    state_entry()
-    {
-        string ___ret__00001;
-        {
-            integer x = 5;
-            {
-                {
-                    ___ret__00001 = "ok";
-                    jump ___rtl__00001;
-                }
-            }
-        }
-        @___rtl__00001;
-        llOwnerSay(___ret__00001);
-    }
-}

unit_tests/coverage.suite/pragma-operator.run

@@ -1 +0,0 @@
-main.py - -O clear,processpre