selftests/kvm: Fix issues with $(SPLIT_TESTS)

The introduction of $(SPLIT_TESTS) also introduced a warning when
building selftests on architectures that include get-reg-lists:

    make: Entering directory '/root/kvm/tools/testing/selftests/kvm'
    Makefile:272: warning: overriding recipe for target '/root/kvm/tools/testing/selftests/kvm/get-reg-list'
    Makefile:267: warning: ignoring old recipe for target '/root/kvm/tools/testing/selftests/kvm/get-reg-list'
    make: Leaving directory '/root/kvm/tools/testing/selftests/kvm'

In addition, the rule for $(SPLIT_TESTS_TARGETS) includes _all_
the $(SPLIT_TESTS_OBJS), which only works because there is just one.
So fix both by adjusting the rules:

- remove $(SPLIT_TESTS_TARGETS) from the $(TEST_GEN_PROGS) rules,
  and rename it to $(SPLIT_TEST_GEN_PROGS)

- fix $(SPLIT_TESTS_OBJS) so that it plays well with $(OUTPUT),
  rename it to $(SPLIT_TEST_GEN_OBJ), and list the object file
  explicitly in the $(SPLIT_TEST_GEN_PROGS) link rule

Fixes: 17da79e0 ("KVM: arm64: selftests: Split get-reg-list test code", 2023-08-09)
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Tested-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Anup Patel <anup@brainfault.org>

tools/testing/selftests/kvm/Makefile

@@ -260,32 +260,36 @@ LIBKVM_C_OBJ := $(patsubst %.c, $(OUTPUT)/%.o, $(LIBKVM_C))
 LIBKVM_S_OBJ := $(patsubst %.S, $(OUTPUT)/%.o, $(LIBKVM_S))
 LIBKVM_STRING_OBJ := $(patsubst %.c, $(OUTPUT)/%.o, $(LIBKVM_STRING))
 LIBKVM_OBJS = $(LIBKVM_C_OBJ) $(LIBKVM_S_OBJ) $(LIBKVM_STRING_OBJ)
-SPLIT_TESTS_TARGETS := $(patsubst %, $(OUTPUT)/%, $(SPLIT_TESTS))
-SPLIT_TESTS_OBJS := $(patsubst %, $(ARCH_DIR)/%.o, $(SPLIT_TESTS))
+SPLIT_TEST_GEN_PROGS := $(patsubst %, $(OUTPUT)/%, $(SPLIT_TESTS))
+SPLIT_TEST_GEN_OBJ := $(patsubst %, $(OUTPUT)/$(ARCH_DIR)/%.o, $(SPLIT_TESTS))
 
 TEST_GEN_OBJ = $(patsubst %, %.o, $(TEST_GEN_PROGS))
 TEST_GEN_OBJ += $(patsubst %, %.o, $(TEST_GEN_PROGS_EXTENDED))
 TEST_DEP_FILES = $(patsubst %.o, %.d, $(TEST_GEN_OBJ))
 TEST_DEP_FILES += $(patsubst %.o, %.d, $(LIBKVM_OBJS))
-TEST_DEP_FILES += $(patsubst %.o, %.d, $(SPLIT_TESTS_OBJS))
+TEST_DEP_FILES += $(patsubst %.o, %.d, $(SPLIT_TEST_GEN_OBJ))
 -include $(TEST_DEP_FILES)
 
-$(TEST_GEN_PROGS) $(TEST_GEN_PROGS_EXTENDED): %: %.o
+x := $(shell mkdir -p $(sort $(OUTPUT)/$(ARCH_DIR) $(dir $(LIBKVM_C_OBJ) $(LIBKVM_S_OBJ))))
+
+$(filter-out $(SPLIT_TEST_GEN_PROGS), $(TEST_GEN_PROGS)) \
+$(TEST_GEN_PROGS_EXTENDED): %: %.o
 	$(CC) $(CFLAGS) $(CPPFLAGS) $(LDFLAGS) $(TARGET_ARCH) $< $(LIBKVM_OBJS) $(LDLIBS) -o $@
 $(TEST_GEN_OBJ): $(OUTPUT)/%.o: %.c
 	$(CC) $(CFLAGS) $(CPPFLAGS) $(TARGET_ARCH) -c $< -o $@
 
-$(SPLIT_TESTS_TARGETS): %: %.o $(SPLIT_TESTS_OBJS)
+$(SPLIT_TEST_GEN_PROGS): $(OUTPUT)/%: $(OUTPUT)/%.o $(OUTPUT)/$(ARCH_DIR)/%.o
 	$(CC) $(CFLAGS) $(CPPFLAGS) $(LDFLAGS) $(TARGET_ARCH) $^ $(LDLIBS) -o $@
+$(SPLIT_TEST_GEN_OBJ): $(OUTPUT)/$(ARCH_DIR)/%.o: $(ARCH_DIR)/%.c
+	$(CC) $(CFLAGS) $(CPPFLAGS) $(TARGET_ARCH) -c $< -o $@
 
 EXTRA_CLEAN += $(GEN_HDRS) \
 	       $(LIBKVM_OBJS) \
-	       $(SPLIT_TESTS_OBJS) \
+	       $(SPLIT_TEST_GEN_OBJ) \
 	       $(TEST_DEP_FILES) \
 	       $(TEST_GEN_OBJ) \
 	       cscope.*
 
-x := $(shell mkdir -p $(sort $(dir $(LIBKVM_C_OBJ) $(LIBKVM_S_OBJ))))
 $(LIBKVM_C_OBJ): $(OUTPUT)/%.o: %.c $(GEN_HDRS)
 	$(CC) $(CFLAGS) $(CPPFLAGS) $(TARGET_ARCH) -c $< -o $@
 
@@ -299,7 +303,7 @@ $(LIBKVM_STRING_OBJ): $(OUTPUT)/%.o: %.c
 	$(CC) $(CFLAGS) $(CPPFLAGS) $(TARGET_ARCH) -c -ffreestanding $< -o $@
 
 x := $(shell mkdir -p $(sort $(dir $(TEST_GEN_PROGS))))
-$(SPLIT_TESTS_OBJS): $(GEN_HDRS)
+$(SPLIT_TEST_GEN_OBJ): $(GEN_HDRS)
 $(TEST_GEN_PROGS): $(LIBKVM_OBJS)
 $(TEST_GEN_PROGS_EXTENDED): $(LIBKVM_OBJS)
 $(TEST_GEN_OBJ): $(GEN_HDRS)