devel/bazel: fix build on powerpc*

bazel uses a bundled abseil. To build on powerpc*, abseil requires a trivial
patch.

In file included from external/com_google_absl/absl/base/internal/unscaledcycleclock.cc:27:
/usr/include/sys/sysctl.h:1185:25: error: unknown type name 'u_int'
int     sysctl(const int *, u_int, void *, size_t *, const void *, size_t);
                            ^
external/com_google_absl/absl/base/internal/unscaledcycleclock.cc:91:10: error: unknown type name 'once_flag'
  static once_flag init_timebase_frequency_once;
         ^
external/com_google_absl/absl/base/internal/unscaledcycleclock.cc:93:18: error: no member named 'LowLevelCallOnce' in namespace 'absl::lts_2020_02_25::base_internal'
  base_internal::LowLevelCallOnce(&init_timebase_frequency_once, [&]() {
  ~~~~~~~~~~~~~~~^

PR:	259056
Approved by:	[email protected] (maintainer)

devel/bazel/Makefile

@@ -49,6 +49,11 @@ FINALRC=	2
 EXTRA_PATCHES+=	${FILESDIR}/extra-i386_tools_cpp_BUILD.static.bsd
 .endif
 
+pre-patch:
+	@${CP} ${FILESDIR}/extra-patch-absl_base_internal_unscaledcycleclock.cc \
+		${FILESDIR}/extra-patch-bazel_grpc__deps.bzl \
+		${WRKSRC}/third_party/grpc/
+
 # Have the location of the system-wide rc file reside ${ETCDIR}.
 # Also adapt the sample file to disable persistent java workers as they
 # do not work reliably on FreeBSD.

devel/bazel/files/extra-patch-absl_base_internal_unscaledcycleclock.cc

@@ -0,0 +1,14 @@
+--- absl/base/internal/unscaledcycleclock.cc.orig	2020-08-09 20:09:49 UTC
++++ absl/base/internal/unscaledcycleclock.cc
+@@ -24,8 +24,10 @@
+ #ifdef __GLIBC__
+ #include <sys/platform/ppc.h>
+ #elif defined(__FreeBSD__)
+-#include <sys/sysctl.h>
++#include "absl/base/call_once.h"
+ #include <sys/types.h>
++#include <sys/sysctl.h>
++#include <threads.h>
+ #endif
+ #endif
+

devel/bazel/files/extra-patch-bazel_grpc__deps.bzl

@@ -0,0 +1,10 @@
+--- a/bazel/grpc_deps.bzl.orig	2021-10-11 15:54:07.083144000 +0200
++++ b/bazel/grpc_deps.bzl	2021-10-11 16:02:48.722952000 +0200
+@@ -239,6 +239,7 @@
+     if "com_google_absl" not in native.existing_rules():
+         http_archive(
+             name = "com_google_absl",
++            patches = ["//third_party/grpc:extra-patch-absl_base_internal_unscaledcycleclock.cc"],
+             sha256 = "f368a8476f4e2e0eccf8a7318b98dafbe30b2600f4e3cf52636e5eb145aba06a",
+             strip_prefix = "abseil-cpp-df3ea785d8c30a9503321a3d35ee7d35808f190d",
+             urls = [

devel/bazel/files/patch-WORKSPACE

@@ -0,0 +1,14 @@
+--- WORKSPACE.orig	2021-10-11 09:54:26 UTC
++++ WORKSPACE
+@@ -1232,7 +1232,10 @@ register_toolchains("//src/main/res:empty_rc_toolchain
+ http_archive(
+     name = "com_github_grpc_grpc",
+     patch_args = ["-p1"],
+-    patches = ["//third_party/grpc:grpc_1.33.1.patch"],
++    patches = [
++	"//third_party/grpc:grpc_1.33.1.patch",
++	"//third_party/grpc:extra-patch-bazel_grpc__deps.bzl",
++    ],
+     sha256 = "58eaee5c0f1bd0b92ebe1fa0606ec8f14798500620e7444726afcaf65041cb63",
+     strip_prefix = "grpc-1.33.1",
+     urls = [