build: link with --orphan-handling=warn

The linker can warn when the linker script does not explicitly place
all sections. These orphan sections are placed according to
heuristics, which may not always be desirable. Enable this warning.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Stewart Smith <stewart@linux.ibm.com>

Makefile.main

@@ -136,6 +136,8 @@ LDFLAGS += -Wl,--no-multi-toc
 LDFLAGS += -mcpu=power7 -mbig-endian -Wl,--oformat,elf64-powerpc
 LDFLAGS_FINAL = -EB -m elf64ppc --no-multi-toc -N --build-id=none --whole-archive
 LDFLAGS_FINAL += -static -nostdlib -pie -Ttext-segment=$(LD_TEXT) --oformat=elf64-powerpc
+LDFLAGS_FINAL += --orphan-handling=warn
+
 LDRFLAGS=-melf64ppc
 # Debug stuff
 #LDFLAGS += -Wl,-v -Wl,-Map,foomap