x86/idt: Make idt_descr static

Commit

  3e77abda ("x86/idt: Consolidate idt functionality")

states that idt_descr could be made static, but it did not actually make
the change. Make it static now.

Fixes: 3e77abda ("x86/idt: Consolidate idt functionality")
Signed-off-by: Jason Andryuk <jandryuk@gmail.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200619205103.30873-1-jandryuk@gmail.com

arch/x86/kernel/idt.c

@@ -160,7 +160,7 @@ static const __initconst struct idt_data apic_idts[] = {
 /* Must be page-aligned because the real IDT is used in the cpu entry area */
 static gate_desc idt_table[IDT_ENTRIES] __page_aligned_bss;
 
-struct desc_ptr idt_descr __ro_after_init = {
+static struct desc_ptr idt_descr __ro_after_init = {
 	.size		= IDT_TABLE_SIZE - 1,
 	.address	= (unsigned long) idt_table,
 };