[build] Balanced partitioning for section ordering

Enable the LLD option for ordering function sections using
balanced partitioning to reduce the compressed binary size
in Fuchsia.

References:
1) RFC:    https://discourse.llvm.org/t/rfc-extending-machos-balanced-partitioning-feature-to-elf/83157
2) PR:     llvm/llvm-project#125559
3) Paper:  https://arxiv.org/abs/2211.09285
4) Talk:   https://www.youtube.com/watch?v=yd4pbSTjwuA&t=1157s

Bug: 460885337
Change-Id: Id8302ed0a7fe1d5afdcff0e39cc0e7b2b5e95ef1
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/7164703
Reviewed-by: Zijie He <[email protected]>
Auto-Submit: Gulfem Savrun Yeniceri <[email protected]>
Reviewed-by: Hans Wennborg <[email protected]>
Commit-Queue: Gulfem Savrun Yeniceri <[email protected]>
Cr-Commit-Position: refs/heads/main@{#1548730}
NOKEYCHECK=True
GitOrigin-RevId: 900b0a15e5d0b41dbc1f9350d3b2f809260cbb36

Author: gulfemsavrun

config/compiler/BUILD.gn

@@ -614,6 +614,13 @@ config("compiler") {
     }
   }
 
+  # Fuchsia-specific compiler flags setup.
+  # ------------------------------------
+  if (is_fuchsia) {
+    # Enable LLD's balanced partitioning for ordering function sections.
+    ldflags += [ "-Wl,--bp-compression-sort=function" ]
+  }
+
   if (is_chromeos_device && current_toolchain == default_toolchain) {
     # Flags added automatically by ChromeOS's custom toolchain that are
     # not already added elsewhere in the configuration. Add these here,