build: adjust setting of QEMU_INCLUDES

Make it correct for nested directories, and move the static part
from Makefile to configure.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Makefile

@@ -145,8 +145,6 @@ audio/audio.o audio/fmodaudio.o: QEMU_CFLAGS += $(FMOD_CFLAGS)
 
 QEMU_CFLAGS+=$(CURL_CFLAGS)
 
-QEMU_CFLAGS += -I$(SRC_PATH)/include
-
 ui/cocoa.o: ui/cocoa.m
 
 ui/sdl.o audio/sdlaudio.o ui/sdl_zoom.o hw/baum.o: QEMU_CFLAGS += $(SDL_CFLAGS)

configure

@@ -278,7 +278,7 @@ QEMU_CFLAGS="-fno-strict-aliasing $QEMU_CFLAGS"
 QEMU_CFLAGS="-Wall -Wundef -Wwrite-strings -Wmissing-prototypes $QEMU_CFLAGS"
 QEMU_CFLAGS="-Wstrict-prototypes -Wredundant-decls $QEMU_CFLAGS"
 QEMU_CFLAGS="-D_GNU_SOURCE -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE $QEMU_CFLAGS"
-QEMU_INCLUDES="-I. -I\$(SRC_PATH) -I\$(SRC_PATH)/fpu"
+QEMU_INCLUDES="-I. -I\$(SRC_PATH) -I\$(SRC_PATH)/include -I\$(SRC_PATH)/fpu"
 if test "$debug_info" = "yes"; then
     CFLAGS="-g $CFLAGS"
     LDFLAGS="-g $LDFLAGS"
@@ -3343,7 +3343,6 @@ fi
 if test "$slirp" = "yes" ; then
   echo "CONFIG_SLIRP=y" >> $config_host_mak
   echo "CONFIG_SMBD_COMMAND=\"$smbd\"" >> $config_host_mak
-  QEMU_INCLUDES="-I\$(SRC_PATH)/slirp $QEMU_INCLUDES"
 fi
 if test "$vde" = "yes" ; then
   echo "CONFIG_VDE=y" >> $config_host_mak

rules.mak

@@ -14,6 +14,9 @@ MAKEFLAGS += -rR
 # Flags for dependency generation
 QEMU_DGFLAGS += -MMD -MP -MT $@ -MF $(*D)/$(*F).d
 
+# Same as -I$(SRC_PATH) -I., but for the nested source/object directories
+QEMU_CFLAGS += -I$(<D) -I$(@D)
+
 %.o: %.c
 	$(call quiet-command,$(CC) $(QEMU_INCLUDES) $(QEMU_CFLAGS) $(QEMU_DGFLAGS) $(CFLAGS) -c -o $@ $<,"  CC    $(TARGET_DIR)$@")