gh-40382: rectify gentoo package name details for lcalc and qhull
    
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URL: #40382
Reported by: Dima Pasechnik
Reviewer(s): Michael Orlitzky

Author: Release Manager

build/pkgs/lcalc/distros/gentoo.txt

@@ -1 +1 @@
-sci-mathematics/lcalc
+sci-mathematics/lcalc[pari]

build/pkgs/qhull/distros/gentoo.txt

@@ -1 +1 @@
-media-libs/qhull
+media-libs/qhull[tools]