Revert "Emit speculation barriers after ERETs"

This reverts commit 366cb48b89ac012a44c3b45cf861649d1c704d42.
Accidentally pushed directly to main tree.

Bug: 146490856
diff --git a/src/arch/aarch64/hypervisor/exceptions.S b/src/arch/aarch64/hypervisor/exceptions.S
index a4c12af..2f47c00 100644
--- a/src/arch/aarch64/hypervisor/exceptions.S
+++ b/src/arch/aarch64/hypervisor/exceptions.S
@@ -518,7 +518,7 @@
 	/* Restore x0..x3, which we have used as scratch before. */
 	ldp x2, x3, [x0, #VCPU_REGS + 8 * 2]
 	ldp x0, x1, [x0, #VCPU_REGS + 8 * 0]
-	eret_with_sb
+	eret
 
 .balign 0x40
 /**
@@ -526,4 +526,4 @@
  */
 restore_from_stack_and_return:
 	restore_volatile_from_stack el2
-	eret_with_sb
+	eret