gawk: Bump to 5.1.0; remove gmp/mpfr.

We don't really need multi-precision-aware Gawk, and this
removes two packages from the base set that are otherwise
unneeded.

sys-apps/gawk/gawk-5.1.0.recipe

@@ -12,11 +12,11 @@ makes it possible to handle simple data-reformatting jobs with just a \
 few lines of code.
 "
 HOMEPAGE="http://www.gnu.org/s/gawk"
-COPYRIGHT="1983-2017 Free Software Foundation, Inc."
+COPYRIGHT="1983-2020 Free Software Foundation, Inc."
 LICENSE="GNU GPL v3"
-REVISION="2"
+REVISION="1"
 SOURCE_URI="https://ftp.gnu.org/gnu/gawk/gawk-$portVersion.tar.gz"
-CHECKSUM_SHA256="625bf3718e25a84dc4486135d5cb5388174682362c70107fd13f21572f5603bb"
+CHECKSUM_SHA256="03a0360edcd84bec156fe211bbc4fc8c78790973ce4e8b990a11d778d40b1a26"
 PATCHES="gawk-$portVersion.patchset"
 
 ARCHITECTURES="!x86_gcc2 ?x86 x86_64 ?arm"
@@ -43,8 +43,6 @@ PROVIDES="
 	"
 REQUIRES="
 	haiku$secondaryArchSuffix
-	lib:libgmp$secondaryArchSuffix
-	lib:libmpfr$secondaryArchSuffix
 	"
 if [ "$targetArchitecture" = x86_gcc2 ]; then
 	CONFLICTS="gawk"
@@ -52,7 +50,6 @@ fi
 
 BUILD_REQUIRES="
 	haiku${secondaryArchSuffix}_devel
-	devel:libmpfr$secondaryArchSuffix
 	"
 BUILD_PREREQUIRES="
 	cmd:awk