package/libgeos: add threads dependency

In Buildroot commit 2dd2f3751ff2aa60df7de5453e65aa148f64645d, the
libgeos package was bumped from 3.9.1 to 3.10.1.

Since version 3.10.0, libgeos uses mutex since (commit https://github.com/libgeos/geos/commit/3fcbd1e0c52843c2ae0b4809c9f89f74ce529afe#diff-38d1bc63228770a179e474aef4fd26b1a2ab5f5758a5d98d07ac556498dd1f3d)

Toolchains without threads support fails to build:
/home/giuliobenetti/autobuild/run/instance-1/output-1/build/libgeos-3.10.1/include/geos/index/strtree/TemplateSTRtree.h:376:10: error: 'mutex' in namespace 'std' does not name a type
  376 |     std::mutex lock_;
      |          ^~~~~

So it needs threads.

Fixes:

 http://autobuild.buildroot.net/results/2d5fe2866dfa24f5747fbc826fea1108a2a6cb47/

Signed-off-by: Maxim Kochetkov <fido_max@inbox.ru>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

package/libgeos/Config.in

@@ -2,6 +2,7 @@ config BR2_PACKAGE_LIBGEOS
 	bool "libgeos"
 	depends on BR2_INSTALL_LIBSTDCPP
 	depends on BR2_USE_WCHAR
+	depends on BR2_TOOLCHAIN_HAS_THREADS
 	depends on !BR2_TOOLCHAIN_HAS_BINUTILS_BUG_21464
 	depends on !BR2_TOOLCHAIN_HAS_BINUTILS_BUG_27597
 	help
@@ -13,7 +14,8 @@ config BR2_PACKAGE_LIBGEOS
 
 	  https://trac.osgeo.org/geos
 
-comment "libgeos needs a toolchain w/ C++, wchar, not binutils bug 21464, 27597"
+comment "libgeos needs a toolchain w/ C++, wchar, threads not binutils bug 21464, 27597"
 	depends on !BR2_INSTALL_LIBSTDCPP || !BR2_USE_WCHAR || \
+		   !BR2_TOOLCHAIN_HAS_THREADS || \
 		   BR2_TOOLCHAIN_HAS_BINUTILS_BUG_21464 || \
 		   BR2_TOOLCHAIN_HAS_BINUTILS_BUG_27597