efi_selftest: do not write to linker generated array

Linker generated arrays may be stored in code sections of memory that are
not writable. So let's allocate setup_ok as an array at runtime.

This avoids an illegal memory access observed in the sandbox.

Reported-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Alexander Graf <agraf@suse.de>

include/efi_selftest.h

@@ -129,7 +129,6 @@ u16 efi_st_get_key(void);
  * @setup:	set up the unit test
  * @teardown:	tear down the unit test
  * @execute:	execute the unit test
- * @setup_ok:	setup was successful (set at runtime)
  * @on_request:	test is only executed on request
  */
 struct efi_unit_test {
@@ -139,7 +138,6 @@ struct efi_unit_test {
 		     const struct efi_system_table *systable);
 	int (*execute)(void);
 	int (*teardown)(void);
-	int setup_ok;
 	bool on_request;
 };