[MIPS] Simplify missing-syscalls for N32 and O32

Use standard missing-syscalls with EXTRA_CFLAGS instead of duplicating
the command. And move the archprepare rule before the archclean rule.
Suggested by Franck Bui-Huu. Also add "echo" to show the target ABI.

Signed-off-by: Atsushi Nemoto <[e-mail]>
Signed-off-by: Ralf Baechle <[e-mail]>

arch/mips/Makefile

···
 CLEAN_FILES += vmlinux.ecoff \
 	       vmlinux.srec
 
+archprepare:
+ifdef CONFIG_MIPS32_N32
+	@echo '  Checking missing-syscalls for N32'
+	$(Q)$(MAKE) $(build)=. missing-syscalls EXTRA_CFLAGS="-mabi=n32"
+endif
+ifdef CONFIG_MIPS32_O32
+	@echo '  Checking missing-syscalls for O32'
+	$(Q)$(MAKE) $(build)=. missing-syscalls EXTRA_CFLAGS="-mabi=32"
+endif
+
 archclean:
 	@$(MAKE) $(clean)=arch/mips/boot
 	@$(MAKE) $(clean)=arch/mips/lasat
···
 CLEAN_FILES += vmlinux.32 \
 	       vmlinux.64 \
 	       vmlinux.ecoff
-
-quiet_cmd_syscalls_n32 = CALL-N32 $<
-      cmd_syscalls_n32 = $(CONFIG_SHELL) $< $(CC) $(c_flags) -mabi=n32
-
-quiet_cmd_syscalls_o32 = CALL-O32 $<
-      cmd_syscalls_o32 = $(CONFIG_SHELL) $< $(CC) $(c_flags) -mabi=32
-
-PHONY += missing-syscalls-n32 missing-syscalls-o32
-
-missing-syscalls-n32: scripts/checksyscalls.sh FORCE
-	$(call cmd,syscalls_n32)
-
-missing-syscalls-o32: scripts/checksyscalls.sh FORCE
-	$(call cmd,syscalls_o32)
-
-archprepare:
-ifdef CONFIG_MIPS32_N32
-	$(Q)$(MAKE) $(build)=arch/mips missing-syscalls-n32
-endif
-ifdef CONFIG_MIPS32_O32
-	$(Q)$(MAKE) $(build)=arch/mips missing-syscalls-o32
-endif