contrib/libosmocore.spec.in: Depends on talloc 2.1.0

With recent commit (see below) libosmocore started using talloc API
talloc_pooled_object(), which is available only startinf from talloc
2.1.0.
Let's bump required version check accordingly.

Issue found by osmo-release.sh:
ERROR: configure.ac <talloc, 2.1.0> does NOT match contrib/*.spec.in <talloc, 2.0.1>!

Fixes: b72867f0e68c96ca25e1f9929ce92be0a802db6b
Change-Id: I6797e244118ce2ca7dd22050ff505d8442bba672
diff --git a/contrib/libosmocore.spec.in b/contrib/libosmocore.spec.in
index df36e89..a3e0601 100644
--- a/contrib/libosmocore.spec.in
+++ b/contrib/libosmocore.spec.in
@@ -29,7 +29,7 @@
 BuildRequires:  pkgconfig(gnutls) >= 2.12.0
 BuildRequires:  pkgconfig(libpcsclite)
 BuildRequires:  pkgconfig(libusb-1.0)
-BuildRequires:  pkgconfig(talloc) >= 2.0.1
+BuildRequires:  pkgconfig(talloc) >= 2.1.0
 BuildRequires:  pkgconfig(libmnl)
 BuildRequires:  pkgconfig(libsystemd)