[bios] Move isolinux definitions to Makefile.pcbios

Signed-off-by: Michael Brown <mcb30@ipxe.org>

src/arch/i386/Makefile

 #
 CFLAGS_lkrnprefix	+= -DVERSION="\"$(VERSION)\""
 
-# Locations of isolinux files
-#
-SYSLINUX_DIR_LIST	:= \
-	/usr/lib/syslinux \
-	/usr/lib/syslinux/bios \
-	/usr/lib/syslinux/modules/bios \
-	/usr/share/syslinux \
-	/usr/share/syslinux/bios \
-	/usr/share/syslinux/modules/bios \
-	/usr/local/share/syslinux \
-	/usr/local/share/syslinux/bios \
-	/usr/local/share/syslinux/modules/bios \
-	/usr/lib/ISOLINUX
-ISOLINUX_BIN_LIST	:= \
-	$(ISOLINUX_BIN) \
-	$(patsubst %,%/isolinux.bin,$(SYSLINUX_DIR_LIST))
-LDLINUX_C32_LIST	:= \
-	$(LDLINUX_C32) \
-	$(patsubst %,%/ldlinux.c32,$(SYSLINUX_DIR_LIST))
-ISOLINUX_BIN	= $(firstword $(wildcard $(ISOLINUX_BIN_LIST)))
-LDLINUX_C32	= $(firstword $(wildcard $(LDLINUX_C32_LIST)))
-
 # i386-specific directories containing source files
 #
 SRCDIRS		+= arch/i386/core arch/i386/transitions arch/i386/prefix

src/arch/i386/Makefile.pcbios

 LIST_NAME_pcirom := ROMS
 LIST_NAME_isarom := ROMS
 
+# Locations of isolinux files
+#
+SYSLINUX_DIR_LIST	:= \
+	/usr/lib/syslinux \
+	/usr/lib/syslinux/bios \
+	/usr/lib/syslinux/modules/bios \
+	/usr/share/syslinux \
+	/usr/share/syslinux/bios \
+	/usr/share/syslinux/modules/bios \
+	/usr/local/share/syslinux \
+	/usr/local/share/syslinux/bios \
+	/usr/local/share/syslinux/modules/bios \
+	/usr/lib/ISOLINUX
+ISOLINUX_BIN_LIST	:= \
+	$(ISOLINUX_BIN) \
+	$(patsubst %,%/isolinux.bin,$(SYSLINUX_DIR_LIST))
+LDLINUX_C32_LIST	:= \
+	$(LDLINUX_C32) \
+	$(patsubst %,%/ldlinux.c32,$(SYSLINUX_DIR_LIST))
+ISOLINUX_BIN	= $(firstword $(wildcard $(ISOLINUX_BIN_LIST)))
+LDLINUX_C32	= $(firstword $(wildcard $(LDLINUX_C32_LIST)))
+
 # rule to make a non-emulation ISO boot image
 NON_AUTO_MEDIA	+= iso
 %iso:	%lkrn util/geniso