soc/sifive/fu540: Makefile: include mtime_init in ramstage

Fix compilation issue
clint.c/mtime.c is needed as well in ramstage due to CR 28372 and 28355

Change-Id: I7c7768744a165b97978bb8f7f95acf7b32ca4aa4
Signed-off-by: Philipp Hug <philipp@hug.cx>
Reviewed-on: https://review.coreboot.org/28551
Tested-by: Patrick Georgi <pgeorgi@google.com>
Reviewed-by: Patrick Georgi <pgeorgi@google.com>

src/soc/lowrisc/lowrisc/Makefile.inc

@@ -3,5 +3,6 @@ ifeq ($(CONFIG_SOC_LOWRISC_LOWRISC),y)
 bootblock-y += mtime.c
 romstage-y += cbmem.c
 ramstage-y += cbmem.c
+ramstage-y += mtime.c
 
 endif

src/soc/sifive/fu540/Makefile.inc

@@ -24,6 +24,7 @@ romstage-y += sdram.c
 romstage-y += otp.c
 
 ramstage-y += uart.c
+ramstage-y += clint.c
 ramstage-y += media.c
 ramstage-y += sdram.c
 ramstage-y += cbmem.c

src/soc/ucb/riscv/Makefile.inc

@@ -3,5 +3,6 @@ ifeq ($(CONFIG_SOC_UCB_RISCV),y)
 bootblock-y += mtime.c
 romstage-y += cbmem.c
 ramstage-y += cbmem.c
+ramstage-y += mtime.c
 
 endif