[LibOS] Move init_r_debug() before init_fs()

Many subsystems (in particular, their error handling paths) rely on
debug metadata (in particular, the lock for debug info) to be already
initialized. For example, previously the FS subsystem might segfault or
fail on assert in the error handling path (if e.g. `fs.insecure__keys`
manifest option could not be parsed).

Signed-off-by: Dmitrii Kuvaiskii <dmitrii.kuvaiskii@intel.com>

libos/src/libos_init.c

@@ -398,14 +398,14 @@ noreturn void libos_init(const char* const* argv, const char* const* envp) {
     }
 
     RUN_INIT(init_vma);
+    RUN_INIT(init_r_debug);
     RUN_INIT(init_slab);
     RUN_INIT(read_environs, envp);
     RUN_INIT(init_rlimit);
     RUN_INIT(init_fs);
     RUN_INIT(init_fs_lock);
     RUN_INIT(init_dcache);
     RUN_INIT(init_handle);
-    RUN_INIT(init_r_debug);
 
     log_debug("LibOS loaded at %p, ready to initialize", &__load_address);