Toolchain+Ports: Split the GCC patches

This shouldn't cause any breaking changes, so a toolchain rebuild is not
required.

As per Hendiadyoin's request, math errno is disabled by default, which
should enable some extra compiler optimizations in LibGL and LibSoftGPU
code that uses math functions heavily.

Co-Authored-By: Ali Mohammad Pur <mpfard@serenityos.org>

Toolchain/Patches/gcc/0004-libgcc-Do-not-link-libgcc_s-to-LibC.patch

@@ -0,0 +1,33 @@
+From c4e0f7d997b3f7cd5c5465a636e097e43170d609 Mon Sep 17 00:00:00 2001
+From: Andreas Kling <awesomekling@gmail.com>
+Date: Mon, 16 May 2022 15:03:14 +0200
+Subject: [PATCH 4/6] libgcc: Do not link libgcc_s to LibC
+
+The toolchain is built before LibC, so linking to the C runtime library
+would fail.
+
+Co-Authored-By: Gunnar Beutner <gbeutner@serenityos.org>
+Co-Authored-By: Daniel Bertalan <dani@danielbertalan.dev>
+Co-Authored-By: Itamar <itamar8910@gmail.com>
+Co-Authored-By: Nico Weber <thakis@chromium.org>
+Co-Authored-By: Philip Herron <herron.philip@googlemail.com>
+Co-Authored-By: Shannon Booth <shannon.ml.booth@gmail.com>
+---
+ libgcc/config/t-slibgcc | 1 -
+ 1 file changed, 1 deletion(-)
+
+diff --git a/libgcc/config/t-slibgcc b/libgcc/config/t-slibgcc
+index 4efd7b43d..932fa0cfb 100644
+--- a/libgcc/config/t-slibgcc
++++ b/libgcc/config/t-slibgcc
+@@ -26,7 +26,6 @@ SHLIB_MAP = @shlib_map_file@
+ SHLIB_OBJS = @shlib_objs@
+ SHLIB_DIR = @multilib_dir@
+ SHLIB_SLIBDIR_QUAL = @shlib_slibdir_qual@
+-SHLIB_LC = -lc
+ SHLIB_MAKE_SOLINK = $(LN_S) $(SHLIB_SONAME) $(SHLIB_DIR)/$(SHLIB_SOLINK)
+ SHLIB_INSTALL_SOLINK = $(LN_S) $(SHLIB_SONAME) \
+ 	$(DESTDIR)$(slibdir)$(SHLIB_SLIBDIR_QUAL)/$(SHLIB_SOLINK)
+-- 
+2.36.1
+