meson: replace create-config with meson configure_file

Move the create-config logic to meson.build; create a
configuration_data object and let meson handle the
quoting and output.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/configure b/configure
index 2186d10..b1889bd 100755
--- a/configure
+++ b/configure
@@ -6962,8 +6962,9 @@
   echo "SLIRP_CFLAGS=$slirp_cflags" >> $config_host_mak
   echo "SLIRP_LIBS=$slirp_libs" >> $config_host_mak
 fi
+subdirs=
 if [ "$slirp" = "git" -o "$slirp" = "internal" ]; then
-    echo "config-host.h: slirp/all" >> $config_host_mak
+  subdirs="$subdirs slirp"
 fi
 if test "$vde" = "yes" ; then
   echo "CONFIG_VDE=y" >> $config_host_mak
@@ -7036,7 +7037,6 @@
   echo "CONFIG_XFS=y" >> $config_host_mak
 fi
 qemu_version=$(head $source_path/VERSION)
-echo "VERSION=$qemu_version" >>$config_host_mak
 echo "PKGVERSION=$pkgversion" >>$config_host_mak
 echo "SRC_PATH=$source_path" >> $config_host_mak
 echo "TARGET_DIRS=$target_list" >> $config_host_mak
@@ -7797,7 +7797,7 @@
 echo "MESON=$meson" >> $config_host_mak
 echo "CC=$cc" >> $config_host_mak
 if $iasl -h > /dev/null 2>&1; then
-  echo "IASL=$iasl" >> $config_host_mak
+  echo "CONFIG_IASL=$iasl" >> $config_host_mak
 fi
 echo "CXX=$cxx" >> $config_host_mak
 echo "OBJCC=$objcc" >> $config_host_mak
@@ -8287,11 +8287,12 @@
 echo "PIXMAN_LIBS=$pixman_libs" >> $config_host_mak
 
 if [ "$fdt" = "git" ]; then
-  echo "config-host.h: dtc/all" >> $config_host_mak
+  subdirs="$subdirs dtc"
 fi
 if [ "$capstone" = "git" -o "$capstone" = "internal" ]; then
-  echo "config-host.h: capstone/all" >> $config_host_mak
+  subdirs="$subdirs capstone"
 fi
+echo "SUBDIRS=$subdirs" >> $config_host_mak
 if test -n "$LIBCAPSTONE"; then
   echo "LIBCAPSTONE=$LIBCAPSTONE" >> $config_host_mak
 fi