package/gcc: select BR2_TOOLCHAIN_HAS_OPENMP if BR2_GCC_ENABLE_OPENMP

BR2_TOOLCHAIN_HAS_OPENMP is also selected by external toolchains, so
can be used by packages to determine OpenMP support.

Signed-off-by: Ed Blake <ed.blake@sondrel.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

package/gcc/Config.in.host

@@ -127,6 +127,7 @@ config BR2_GCC_ENABLE_LTO
 config BR2_GCC_ENABLE_OPENMP
 	bool "Enable compiler OpenMP support"
 	depends on !BR2_PTHREADS_NONE && !BR2_arc && !BR2_microblaze
+	select BR2_TOOLCHAIN_HAS_OPENMP
 	help
 	  Enable OpenMP support for the compiler