package/glibc, toolchain/toolchain-buildroot: disable native RPC in glibc toolchains

Support for obsolete RPC was dropped in glibc 2.14 (2011-05-31), then
reinstated and marked obsolete in glibc 2.16 (2012-06-30), and finally
dropped for good in 2.32 (2020-08-04), which we are about to start
using.

In preparation for that, drop the usage of obsolete RPC support in
glibc.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
[yann.morin.1998@free.fr: add a bit of history]
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>

package/glibc/glibc.mk

@@ -137,7 +137,6 @@ define GLIBC_CONFIGURE_CMDS
 		--disable-profile \
 		--disable-werror \
 		--without-gd \
-		--enable-obsolete-rpc \
 		--enable-kernel=$(call qstrip,$(BR2_TOOLCHAIN_HEADERS_AT_LEAST)) \
 		--with-headers=$(STAGING_DIR)/usr/include)
 	$(GLIBC_ADD_MISSING_STUB_H)

toolchain/toolchain-buildroot/Config.in

@@ -60,9 +60,6 @@ config BR2_TOOLCHAIN_BUILDROOT_GLIBC
 	depends on !BR2_powerpc_SPE
 	depends on BR2_RISCV_ISA_RVA || !BR2_riscv
 	select BR2_TOOLCHAIN_USES_GLIBC
-	# our glibc.mk enables RPC support, except for riscv32 and arc
-	# that don't have it anymore (glibc 2.32+)
-	select BR2_TOOLCHAIN_HAS_NATIVE_RPC if !BR2_RISCV_32 && !BR2_arc
 	help
 	  This option selects glibc as the C library for the
 	  cross-compilation toolchain.