package/squid: needs C++17

C++17 is mandatory since bump to version 6.2 in commit
2a7c6816f02f45946e896577d78e3470331b2d63 and
https://github.com/squid-cache/squid/commit/09835feb258c3058d028918e36d959dccb3f7496
resulting in the following build failure:

configure: error: *** A compiler with support for C++17 language features is required.

Fixes: 2a7c6816f02f45946e896577d78e3470331b2d63
 - http://autobuild.buildroot.org/results/06755c324f0bf37e52976fce48a5ad62915193da

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/squid/Config.in

@@ -1,10 +1,10 @@
-comment "squid needs a toolchain w/ C++, threads, gcc >= 4.8 not affected by bug 64735"
+comment "squid needs a toolchain w/ C++, threads, gcc >= 7 not affected by bug 64735"
 	depends on BR2_USE_MMU
 	depends on BR2_TOOLCHAIN_HAS_ATOMIC
 	depends on BR2_TOOLCHAIN_HAS_GCC_BUG_64735 || \
 		!BR2_INSTALL_LIBSTDCPP || \
 		!BR2_TOOLCHAIN_HAS_THREADS || \
-		!BR2_TOOLCHAIN_GCC_AT_LEAST_4_8
+		!BR2_TOOLCHAIN_GCC_AT_LEAST_7
 
 config BR2_PACKAGE_SQUID
 	bool "squid"
@@ -12,7 +12,7 @@ config BR2_PACKAGE_SQUID
 	depends on BR2_INSTALL_LIBSTDCPP
 	depends on BR2_TOOLCHAIN_HAS_THREADS
 	depends on !BR2_TOOLCHAIN_HAS_GCC_BUG_64735 # std::current_exception
-	depends on BR2_TOOLCHAIN_GCC_AT_LEAST_4_8 # C++11
+	depends on BR2_TOOLCHAIN_GCC_AT_LEAST_7 # C++17
 	# needs fork()
 	depends on BR2_USE_MMU
 	select BR2_PACKAGE_LIBCAP