dhcp/ruby/ffpmeg: Use CFLAGS, not TARGET_CFLAGS

There isn't anything specific about the target in these cases an in
general recipes should touch CFLAGS. This ensures people don't
copy/paste bad example usages. In reality, behaviour is mostly
unchanged.

(From OE-Core rev: ae6e7dd19b6da81090a38792dfdf31b459290466)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-connectivity/dhcp/dhcp.inc

@@ -43,7 +43,7 @@ INITSCRIPT_PACKAGES = "dhcp-server"
 INITSCRIPT_NAME_dhcp-server = "dhcp-server"
 INITSCRIPT_PARAMS_dhcp-server = "defaults"
 
-TARGET_CFLAGS += "-D_GNU_SOURCE"
+CFLAGS += "-D_GNU_SOURCE"
 EXTRA_OECONF = "--with-srv-lease-file=${localstatedir}/lib/dhcp/dhcpd.leases \
                 --with-srv6-lease-file=${localstatedir}/lib/dhcp/dhcpd6.leases \
                 --with-cli-lease-file=${localstatedir}/lib/dhcp/dhclient.leases \

meta/recipes-devtools/ruby/ruby.inc

@@ -35,6 +35,6 @@ inherit autotools ptest
 # built.
 
 do_configure_prepend() {
-    sed -i "s#%%TARGET_CFLAGS%%#$TARGET_CFLAGS#; s#%%TARGET_LDFLAGS%%#$TARGET_LDFLAGS#" ${S}/common.mk
+    sed -i "s#%%TARGET_CFLAGS%%#$CFLAGS#; s#%%TARGET_LDFLAGS%%#$LDFLAGS#" ${S}/common.mk
     rm -rf ${S}/ruby/
 }

meta/recipes-multimedia/ffmpeg/ffmpeg_4.2.1.bb

@@ -102,8 +102,8 @@ EXTRA_OECONF = " \
     --arch=${TARGET_ARCH} \
     --target-os="linux" \
     --enable-cross-compile \
-    --extra-cflags="${TARGET_CFLAGS} ${HOST_CC_ARCH}${TOOLCHAIN_OPTIONS}" \
-    --extra-ldflags="${TARGET_LDFLAGS}" \
+    --extra-cflags="${CFLAGS} ${HOST_CC_ARCH}${TOOLCHAIN_OPTIONS}" \
+    --extra-ldflags="${LDFLAGS}" \
     --sysroot="${STAGING_DIR_TARGET}" \
     ${EXTRA_FFCONF} \
     --libdir=${libdir} \