arm/tclibc: add spaces after TCLIBC

Seeing the warning:
  lack of whitespace around the assignment: 'TCLIBC="musl"'

Add spaces to address the issue

Signed-off-by: Jon Mason <jon.mason@arm.com>

kas/corstone1000-firmware-only.yml

@@ -10,7 +10,7 @@ local_conf_header:
     OVERRIDES .= ":firmware"
 
     # Need to ensure we build with a small libc
-    TCLIBC="musl"
+    TCLIBC = "musl"
 
   mass-storage: |
     # Ensure the Mass Storage device is absent

meta-arm/conf/multiconfig/firmware.conf

@@ -4,7 +4,7 @@
 DISTROOVERRIDES = "firmware"
 
 TMPDIR:append = "_${MACHINE}"
-TCLIBC="musl"
+TCLIBC = "musl"
 
 # Ignore the testimage flags to include ssh-server-dropbear
 IMAGE_CLASSES:remove = "testimage"