gh-35083: build/pkgs/pcre: Remove

    
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### 📚 Description

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Remove the spkg `pcre`; it was a dependency of our `r` package, which
was reduced to a dummy package recently.
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Closes #32231

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URL: #35083
Reported by: Matthias Köppe
Reviewer(s): Dima Pasechnik

build/pkgs/_prereq/distros/fedora.txt

@@ -30,7 +30,6 @@ gcc-c++
 # The need for which comes [...] from MPIR's configure script
 findutils
 which
-# Needed for pcre configure, see /~https://github.com/sagemath/sage/issues/29129:
 diffutils
 # Needed for openssl 3.0
 perl-IPC-Cmd

build/pkgs/r/SPKG.rst

@@ -24,15 +24,3 @@ Upstream Contact
 
 -  https://www.r-project.org
 -  R mailing list, #R in IRC
-
-Dependencies
-------------
-
--  GNU patch
--  iconv
--  Readline
--  BLAS/LAPACK
--  xz
--  pcre
--  curl
--  https-capable SSL

configure.ac

@@ -487,7 +487,7 @@ AS_IF([test "$SAGE_ENABLE_notebook" = no -a "$SAGE_ENABLE_sagelib" = no], [
 AC_ARG_ENABLE([r],
   AS_HELP_STRING([--disable-r],
                  [disable build of the R package and related packages]), [
-    for pkg in r rpy2 r_jupyter pcre; do
+    for pkg in r rpy2 r_jupyter; do
       AS_VAR_SET([SAGE_ENABLE_$pkg], [$enableval])
     done
   ])