Revert "Related: rhbz#2121654 Work around pkgconfig(libpq) conflict"

This reverts commit 5f24abf444, which is no longer
needed after
<224667bda0>
"Do not provide pkgconfig(libpq) from postgresql-private-devel to not trick
packages that actually require libpq-devel" on rawhide

libreoffice.spec

@@ -138,7 +138,6 @@ BuildRequires: firebird-devel
 BuildRequires: glm-devel
 BuildRequires: hyphen-devel
 BuildRequires: libjpeg-turbo-devel
-BuildRequires: libpq-devel
 BuildRequires: lpsolve-devel
 BuildRequires: openldap-devel
 BuildRequires: pam-devel
@@ -171,6 +170,7 @@ BuildRequires: pkgconfig(libmspub-0.1)
 BuildRequires: pkgconfig(libmwaw-0.3)
 BuildRequires: pkgconfig(libodfgen-0.1)
 BuildRequires: pkgconfig(libpagemaker-0.0)
+BuildRequires: pkgconfig(libpq)
 BuildRequires: pkgconfig(librevenge-0.0)
 BuildRequires: pkgconfig(libstaroffice-0.0)
 BuildRequires: pkgconfig(libtiff-4)