File _multibuild of Package gcc11

<multibuild>
<flavor>gcc11-testresults</flavor>
<flavor>cross-aarch64-gcc11-bootstrap</flavor>
<flavor>cross-aarch64-gcc11</flavor>
<flavor>cross-riscv64-gcc11-bootstrap</flavor>
<flavor>cross-riscv64-gcc11</flavor>
<flavor>cross-arm-gcc11</flavor>
<flavor>cross-avr-gcc11-bootstrap</flavor>
<flavor>cross-avr-gcc11</flavor>
<flavor>cross-x86_64-gcc11</flavor>
<flavor>cross-s390x-gcc11</flavor>
<flavor>cross-sparc-gcc11</flavor>
<flavor>cross-sparc64-gcc11</flavor>
<flavor>cross-ppc64-gcc11</flavor>
<flavor>cross-ppc64le-gcc11</flavor>
<flavor>cross-m68k-gcc11</flavor>
<flavor>cross-mips-gcc11</flavor>
<flavor>cross-hppa-gcc11</flavor>
<flavor>cross-arm-none-gcc11-bootstrap</flavor>
<flavor>cross-arm-none-gcc11</flavor>
<flavor>cross-epiphany-gcc11-bootstrap</flavor>
<flavor>cross-epiphany-gcc11</flavor>
<flavor>cross-riscv64-elf-gcc11-bootstrap</flavor>
<flavor>cross-riscv64-elf-gcc11</flavor>
<flavor>cross-rx-gcc11-bootstrap</flavor>
<flavor>cross-rx-gcc11</flavor>
<flavor>cross-nvptx-gcc11</flavor>
<flavor>cross-amdgcn-gcc11</flavor>
</multibuild>