Remove undefined symbols from version script.

Bug: https://bugs.gentoo.org/925578
--- a/renderdoc/renderdoc.version
+++ b/renderdoc/renderdoc.version
@@ -6,17 +6,14 @@
                 egl[A-Z]*;
                 vk_icd*;
                 dlopen;
-                dlsym;
                 fork;
                 execl;
                 execlp;
                 execle;
-                execlpe;
                 execv;
                 execvp;
                 execve;
                 execvpe;
-                _exit;
                 RENDERDOC_*;
                 VK_LAYER_RENDERDOC_*;
         local: