x86: Convert to use driver model timer

Convert all x86 boards to use driver model tsc timer.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Simon Glass <sjg@chromium.org>
diff --git a/configs/efi-x86_defconfig b/configs/efi-x86_defconfig
index 2daab36..3b81046 100644
--- a/configs/efi-x86_defconfig
+++ b/configs/efi-x86_defconfig
@@ -14,4 +14,6 @@
 CONFIG_DEBUG_UART_BASE=0
 CONFIG_DEBUG_UART_CLOCK=0
 CONFIG_ICH_SPI=y
+# CONFIG_X86_SERIAL is not set
+CONFIG_TIMER=y
 CONFIG_EFI=y