efirt: Move comment about fpu_kern_enter to where it is called

Reviewed by:	imp, kib, andrew, markj
Differential Revision:	https://reviews.freebsd.org/D41576

(cherry picked from commit 8173fa60ddb7e9a805dec9fef7bf07e74ae4144d)

sys/amd64/amd64/efirt_machdep.c

@@ -280,11 +280,6 @@ fail:
  * reason to bother with the virtual map, and no need to add a
  * complexity into loader.
  *
- * The fpu_kern_enter() call allows firmware to use FPU, as mandated
- * by the specification.  In particular, CR0.TS bit is cleared.  Also
- * it enters critical section, giving us neccessary protection against
- * context switch.
- *
  * There is no need to disable interrupts around the change of %cr3,
  * the kernel mappings are correct, while we only grabbed the
  * userspace portion of VA.  Interrupts handlers must not access

sys/dev/efidev/efirt.c

@@ -285,6 +285,11 @@ rt_ok(void)
 	return (0);
 }
 
+/*
+ * The fpu_kern_enter() call in allows firmware to use FPU, as
+ * mandated by the specification.  It also enters a critical section,
+ * giving us neccessary protection against context switches.
+ */
 static int
 efi_enter(void)
 {