Toolchain: Fix building libgcc for AARCH64

There was a typo in one of the spec files which resulted in us not
building softfp support for libgcc. Additionally we were missing flags
to build libgcc_s. This patch also makes sure we're not trying to
link against crtbeginS.o and crtendS.o. This is part of a larger effort
to at least get the userland to build at all.

Toolchain/Patches/gcc/0001-Add-a-gcc-driver-for-SerenityOS.patch

@@ -101,11 +101,11 @@ index 0000000000000000000000000000000000000000..17551aaa1a07e6c0b7365f9889937512
 +/* Files that are linked before user code.
 +   The %s tells GCC to look for these files in the library directory. */
 +#undef STARTFILE_SPEC
-+#define STARTFILE_SPEC "%{!shared:crt0.o%s} crti.o%s %{shared: %{!fbuilding-libgcc:crt0_shared.o%s}} %{shared|static-pie|!no-pie:crtbeginS.o%s; :crtbegin.o%s}"
++#define STARTFILE_SPEC "%{!shared:crt0.o%s} crti.o%s %{shared: %{!fbuilding-libgcc:crt0_shared.o%s}} %{shared|static-pie|!no-pie:%:if-exists-else(crtbeginS.o%s crtbegin.o%s); :crtbegin.o%s}"
 +
 +/* Files that are linked after user code. */
 +#undef ENDFILE_SPEC
-+#define ENDFILE_SPEC "%{shared|static-pie|!no-pie:crtendS.o%s; :crtend.o%s} crtn.o%s"
++#define ENDFILE_SPEC "%{shared|static-pie|!no-pie:%:if-exists-else(crtendS.o%s crtend.o%s); :crtend.o%s} crtn.o%s"
 +
 +#undef LINK_SPEC
 +#define LINK_SPEC "%{shared:-shared} %{static:-static} %{!static: %{rdynamic:-export-dynamic} -dynamic-linker /usr/lib/Loader.so}"

Toolchain/Patches/gcc/0003-libgcc-Build-for-SerenityOS.patch

@@ -53,8 +53,8 @@ index 8c56fcae5d2fdfcc8d1f9b2614f0c41ad44f258f..f5855cfa66d7950c3d7565ad938b4e47
 +	extra_parts="$extra_parts crti.o crtbegin.o crtend.o crtn.o"
 +	extra_parts="$extra_parts crtfastmath.o"
 +	tmake_file="$tmake_file ${cpu_type}/t-aarch64"
-+	tmake_file="$tmake_file ${cpu_type}/t-lse t-slibgcc-libgcc"
-+	tmake_file="$tmake_file ${cpu_type}/t-softfp t-softp t-crtfm"
++	tmake_file="$tmake_file ${cpu_type}/t-lse t-slibgcc t-slibgcc-libgcc"
++	tmake_file="$tmake_file ${cpu_type}/t-softfp t-softfp t-crtfm"
 +	md_unwind_header=aarch64/aarch64-unwind.h
 +	;;
  *)