Examinc OPT and CROSSOPT instead of FPCOPT in [prerules] to check if syscall unit needs objpas dependency

rtl/linux/Makefile

@@ -907,8 +907,8 @@ else
 SYSCALL_DEPS_OS=$(ARCH)/syscallh.inc $(ARCH)/sysnr.inc
 endif
 endif
-ifneq ($(filter -dFPC_USE_LIBC,$(FPCOPT)),)
-  SYSCALL_DEPS_OS+=$(OBJPASUNITUNIT)$(PPUEXT)
+ifneq ($(filter -dFPC_USE_LIBC,$(OPT) $(CROSSOPT)),)
+  SYSCALL_DEPS_OS+=$(OBJPASUNIT)$(PPUEXT)
 endif
 SYSUTILSDIR=$(UNIXINC)
 SYSUTILS_DEPS_OS=$(SYSUTILS_UNIX_DEPS) $(LINUXUNIT)$(PPUEXT)

rtl/linux/Makefile.fpc

@@ -79,8 +79,8 @@ endif
 # syscall unit compiled with -dFPC_USE_LIBC
 # required mode objfpc which adds a dependency to
 # objpas unit 
-ifneq ($(filter -dFPC_USE_LIBC,$(FPCOPT)),)
-  SYSCALL_DEPS_OS+=$(OBJPASUNITUNIT)$(PPUEXT)
+ifneq ($(filter -dFPC_USE_LIBC,$(OPT) $(CROSSOPT)),)
+  SYSCALL_DEPS_OS+=$(OBJPASUNIT)$(PPUEXT)
 endif
 
 SYSUTILSDIR=$(UNIXINC)