feat(decomp): bank main:func_8005D538 from the S77w wave

Plain C, no §265 verbatim needed — the pack's prior FAILED attempt had
over-thought it. Two levers: omit the forward decl for func_8005E188 so the
call is implicit K&R (fixing both an s0/s1 order swap and a spurious
sign-extend a visible prototype would insert), and close the 2 trailing pad
words with a file-scope __asm__ per the §295 class.

gate_main: BANKED 1, 143dbb89f34491258bbc27810d0a12ec8b43a8dd BYTE-IDENTICAL.

src/800c3.c

@@ -494,7 +494,12 @@ void func_8005D4F0(s32 arg0, s32 arg1, s32 arg2) {
     func_8005E8E8(D_80072970(), (u8)arg1, (u8)arg2);
 }
 
-INCLUDE_ASM("asm/nonmatchings/800c3", func_8005D538);
+extern void* (*D_80072970)(void);
+
+void func_8005D538(s32 arg0, void *arg1, s32 arg2) {
+    func_8005E188(D_80072970(), arg1, arg2);
+}
+__asm__("nop\nnop\n");