Fix u-boot ppc jamfile

* fix leftover openfirmware stuff from copy-paste.
* shell.S is still missing.

src/system/boot/platform/u-boot/arch/ppc/Jamfile

@@ -1,18 +1,23 @@
-SubDir HAIKU_TOP src system boot platform openfirmware arch ppc ;
+SubDir HAIKU_TOP src system boot platform u-boot arch ppc ;
 
 SubDirHdrs $(HAIKU_TOP) src system boot platform $(TARGET_BOOT_PLATFORM) ;
 UsePrivateSystemHeaders ;
 UsePrivateHeaders kernel [ FDirName kernel arch $(TARGET_ARCH) ] 
 	[ FDirName kernel boot platform $(HAIKU_BOOT_PLATFORM) ] ;
+UsePrivateHeaders [ FDirName kernel arch $(TARGET_ARCH) board $(TARGET_BOOT_BOARD) ] ;
 
 SubDirC++Flags -fno-rtti ;
 
-KernelStaticLibrary boot_platform_openfirmware_ppc :
-	arch_mmu.cpp
-	arch_cpu_asm.S
+KernelMergeObject boot_platform_u-boot_ppc.o :
+	# must come first to have _start_* at correct locations
+	shell.S
+
+	#arch_mmu.cpp
+	#arch_cpu_asm.S
 	arch_start_kernel.S
-	cpu.cpp
-	mmu.cpp
+	#cpu.cpp
+	#mmu.cpp
+	: -fno-pic
 ;
 
 SEARCH on [ FGristFiles arch_cpu_asm.S arch_mmu.cpp ]