Add kelvin sim renode library to simulation targets' prereqs

We need to build kelvin_sim library to support running e2e system
simulation.

Change-Id: I9befbf15495cf584a7a3c3a0b2e187a7bba83e50

platforms/nexus/sim.mk

diff --git a/platforms/nexus/sim.mk b/platforms/nexus/sim.mk
index a472161..26fec08 100644
--- a/platforms/nexus/sim.mk
+++ b/platforms/nexus/sim.mk
@@ -73,7 +73,7 @@
 #
 # This is the default target for the build system, and is generally what you
 # need for day-to-day work on the software side of Shodan.
-simulate: renode multihart_boot_rom ext_flash_release kelvin_hello_world cantrip-builtins-release
+simulate: renode kelvin_sim multihart_boot_rom ext_flash_release kelvin_hello_world cantrip-builtins-release
 	$(RENODE_CMD) -e "\
     \$$repl_file = @sim/config/platforms/nexus.repl; \
     \$$tar = @$(EXT_FLASH_RELEASE); \
@@ -90,7 +90,7 @@
 # cpu0, and uses the debug build of TockOS from the `matcha_tock_debug` target.
 #
 # NB: requires editing of platform.camkes for alternate cpio_load_address
-simulate-debug: renode multihart_boot_rom ext_flash_debug iree_model_builtins cantrip-builtins-debug
+simulate-debug: renode kelvin_sim multihart_boot_rom ext_flash_debug iree_model_builtins cantrip-builtins-debug
 	$(RENODE_CMD) -e "\
     \$$repl_file = @sim/config/platforms/nexus-debug.repl; \
     \$$tar = @$(EXT_FLASH_DEBUG); \
@@ -108,7 +108,7 @@
 # start.
 #
 # NB: requires editing of platform.camkes for alternate cpio_load_address
-debug-simulation: renode multihart_boot_rom ext_flash_debug iree_model_builtins cantrip-builtins-debug
+debug-simulation: renode kelvin_sim multihart_boot_rom ext_flash_debug iree_model_builtins cantrip-builtins-debug
 	$(RENODE_CMD) -e "\
     \$$repl_file = @sim/config/platforms/nexus-debug.repl; \
     \$$tar = @$(EXT_FLASH_DEBUG); \