build: convert some obj-specific CFLAGS to use new foo.o-cflags syntax

Current Makefile system allows using foo.o-cflags variables to store
object-specific CFLAGS.  Convert some usages of old syntax
(using QEMU_CFLAGS += construct) to the new syntax.

Do not touch multifile modules for now, as build system isn't ready for this.
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Makefile

@@ -148,10 +148,6 @@ endif
 
 all: $(DOCS) $(TOOLS) $(HELPERS-y) recurse-all modules
 
-vl.o: QEMU_CFLAGS+=$(GPROF_CFLAGS)
-
-vl.o: QEMU_CFLAGS+=$(SDL_CFLAGS)
-
 config-host.h: config-host.h-timestamp
 config-host.h-timestamp: config-host.mak
 qemu-options.def: $(SRC_PATH)/qemu-options.hx
@@ -195,8 +191,6 @@ ALL_SUBDIRS=$(TARGET_DIRS) $(patsubst %,pc-bios/%, $(ROMS))
 
 recurse-all: $(SUBDIR_RULES) $(ROMSUBDIR_RULES)
 
-bt-host.o: QEMU_CFLAGS += $(BLUEZ_CFLAGS)
-
 $(BUILD_DIR)/version.o: $(SRC_PATH)/version.rc $(BUILD_DIR)/config-host.h | $(BUILD_DIR)/version.lo
 	$(call quiet-command,$(WINDRES) -I$(BUILD_DIR) -o $@ $<,"  RC    version.o")
 $(BUILD_DIR)/version.lo: $(SRC_PATH)/version.rc $(BUILD_DIR)/config-host.h

Makefile.objs

@@ -64,9 +64,11 @@ common-obj-y += hw/
 
 common-obj-y += ui/
 common-obj-y += bt-host.o bt-vhci.o
+bt-host.o-cflags := $(BLUEZ_CFLAGS)
 
 common-obj-y += dma-helpers.o
 common-obj-y += vl.o
+vl.o-cflags := $(GPROF_CFLAGS) $(SDL_CFLAGS)
 common-obj-y += tpm.o
 
 common-obj-$(CONFIG_SLIRP) += slirp/

audio/Makefile.objs

@@ -14,4 +14,4 @@ common-obj-$(CONFIG_AUDIO_WIN_INT) += audio_win_int.o
 common-obj-y += wavcapture.o
 
 $(obj)/audio.o $(obj)/fmodaudio.o: QEMU_CFLAGS += $(FMOD_CFLAGS)
-$(obj)/sdlaudio.o: QEMU_CFLAGS += $(SDL_CFLAGS)
+sdlaudio.o-cflags := $(SDL_CFLAGS)

backends/Makefile.objs

@@ -3,6 +3,6 @@ common-obj-$(CONFIG_POSIX) += rng-random.o
 
 common-obj-y += msmouse.o
 common-obj-$(CONFIG_BRLAPI) += baum.o
-$(obj)/baum.o: QEMU_CFLAGS += $(SDL_CFLAGS) 
+baum.o-cflags := $(SDL_CFLAGS)
 
 common-obj-$(CONFIG_TPM) += tpm.o

disas/Makefile.objs

@@ -4,7 +4,7 @@ common-obj-$(CONFIG_ARM_DIS) += arm.o
 common-obj-$(CONFIG_ARM_A64_DIS) += arm-a64.o
 common-obj-$(CONFIG_ARM_A64_DIS) += libvixl/
 libvixldir = $(SRC_PATH)/disas/libvixl
-$(obj)/arm-a64.o: QEMU_CFLAGS += -I$(libvixldir)
+arm-a64.o-cflags := -I$(libvixldir)
 common-obj-$(CONFIG_CRIS_DIS) += cris.o
 common-obj-$(CONFIG_HPPA_DIS) += hppa.o
 common-obj-$(CONFIG_I386_DIS) += i386.o

ui/Makefile.objs

@@ -17,4 +17,4 @@ common-obj-$(CONFIG_GTK) += gtk.o x_keymap.o
 
 $(obj)/sdl.o $(obj)/sdl_zoom.o $(obj)/sdl2.o: QEMU_CFLAGS += $(SDL_CFLAGS)
 
-$(obj)/gtk.o: QEMU_CFLAGS += $(GTK_CFLAGS) $(VTE_CFLAGS)
+gtk.o-cflags := $(GTK_CFLAGS) $(VTE_CFLAGS)