hv: rename cpu_secondary.S to trampline.S

We will reuse this part of code for:
   - AP bootup
   - BSP wakeup from S3

Signed-off-by: Yin Fengwei <fengwei.yin@intel.com>
Acked-by: Anthony Xu <anthony.xu@intel.com>
Acked-by: Eddie Dong <Eddie.dong@intel.com>

Author: fyin1

hypervisor/Makefile

@@ -82,7 +82,7 @@ C_SRCS += boot/acpi.c
 C_SRCS += boot/dmar_parse.c
 C_SRCS += arch/x86/ioapic.c
 C_SRCS += arch/x86/intr_lapic.c
-S_SRCS += arch/x86/cpu_secondary.S
+S_SRCS += arch/x86/trampline.S
 C_SRCS += arch/x86/cpu.c
 C_SRCS += arch/x86/softirq.c
 C_SRCS += arch/x86/cpuid.c