mariadb: remove darwin patch that no longer applies

Hopefully it isn't needed anymore.

pkgs/servers/sql/mariadb/default.nix

@@ -29,8 +29,6 @@ common = rec { # attributes common to both builds
     sed -i 's,[^"]*/var/log,/var/log,g' storage/mroonga/vendor/groonga/CMakeLists.txt
   '';
 
-  patches = stdenv.lib.optional stdenv.isDarwin ./my_context_asm.patch;
-
   nativeBuildInputs = [ cmake pkgconfig ];
 
   buildInputs = [

pkgs/servers/sql/mariadb/my_context_asm.patch

@@ -1,18 +0,0 @@
---- a/mysys/my_context.c
-+++ b/mysys/my_context.c
-@@ -206,15 +206,6 @@ my_context_spawn(struct my_context *c, void (*f)(void *), void *d)
-     (
-      "movq %%rsp, (%[save])\n\t"
-      "movq %[stack], %%rsp\n\t"
--#if __GNUC__ >= 4 && __GNUC_MINOR__ >= 4 && !defined(__INTEL_COMPILER)
--     /*
--       This emits a DWARF DW_CFA_undefined directive to make the return address
--       undefined. This indicates that this is the top of the stack frame, and
--       helps tools that use DWARF stack unwinding to obtain stack traces.
--       (I use numeric constant to avoid a dependency on libdwarf includes).
--     */
--     ".cfi_escape 0x07, 16\n\t"
--#endif
-      "movq %%rbp, 8(%[save])\n\t"
-      "movq %%rbx, 16(%[save])\n\t"
-      "movq %%r12, 24(%[save])\n\t"