There's a merged pull request on the void-packages repository

gnuradio: remove mpir-devel from makedepends
https://github.com/void-linux/void-packages/pull/41535

Description:
This was never used for building or runtime, gmp is used instead.

No need to revbump since this will make no difference (other than dropping mpir-devel from gnuradio-devel depends).

This is the only dependency of mpir in void linux.

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