overlay profiles: Disable mpfr for sys-apps/gawk

After the update, the USE=mpfr got enabled by default, so now we need
to disable it explicitly. Gawk is a part of our initrd, which means
that mpfr gets pulled into it now, increasing the size of it by
another 2mb, which breaks Flatcar updates.

Author: krnowak

sdk_container/src/third_party/coreos-overlay/profiles/coreos/base/package.use

@@ -196,3 +196,7 @@ sys-libs/libcap static-libs
 
 # do not force a dependency on llvm-core/llvm yet
 dev-lang/rust -system-llvm
+
+# disable mpfr in gawk, this ends up being pulled into initrd, making
+# it grow by another 2mb
+sys-apps/gawk -mpfr