gh-41093: Update maxima package use flags for Gentoo
    
makes sure maxima on Gentoo is maxima[ecl], not maxima[sbcl]
See https://bugs.gentoo.org/964693

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URL: #41093
Reported by: Dima Pasechnik
Reviewer(s): Michael Orlitzky

Author: Release Manager

build/pkgs/maxima/distros/gentoo.txt

@@ -1,2 +1 @@
-sci-mathematics/maxima[ecl]
-
+sci-mathematics/maxima[-sbcl,-clozurecl,-clozurecl64,-gcl,-clisp,ecl]