x86/microcode: Remove redundant __setup() param parsing

We do parse for the disable microcode loader chicken bit very early.
After the driver merge, the __setup() param parsing method is not needed
anymore so get rid of it.

In addition, fix a compiler warning from an old SLES11 gcc (4.3.4)
reported by Jan Beulich <jbeulich@suse.com>:

  arch/x86/kernel/cpu/microcode/core.c: In function ‘load_ucode_bsp’:
  arch/x86/kernel/cpu/microcode/core.c:96: warning: array subscript is above array bounds
Tested-by: Thomas Voegtle <tv@lio96.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1454499225-21544-4-git-send-email-bp@alien8.deSigned-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/kernel/cpu/microcode/core.c

@@ -43,16 +43,8 @@
 #define MICROCODE_VERSION	"2.01"
 
 static struct microcode_ops	*microcode_ops;
-
 static bool dis_ucode_ldr;
 
-static int __init disable_loader(char *str)
-{
-	dis_ucode_ldr = true;
-	return 1;
-}
-__setup("dis_ucode_ldr", disable_loader);
-
 /*
  * Synchronization.
  *
@@ -81,15 +73,16 @@ struct cpu_info_ctx {
 
 static bool __init check_loader_disabled_bsp(void)
 {
+	static const char *__dis_opt_str = "dis_ucode_ldr";
+
 #ifdef CONFIG_X86_32
 	const char *cmdline = (const char *)__pa_nodebug(boot_command_line);
-	const char *opt	    = "dis_ucode_ldr";
-	const char *option  = (const char *)__pa_nodebug(opt);
+	const char *option  = (const char *)__pa_nodebug(__dis_opt_str);
 	bool *res = (bool *)__pa_nodebug(&dis_ucode_ldr);
 
 #else /* CONFIG_X86_64 */
 	const char *cmdline = boot_command_line;
-	const char *option  = "dis_ucode_ldr";
+	const char *option  = __dis_opt_str;
 	bool *res = &dis_ucode_ldr;
 #endif