External ARM9 payload chainloading for a9lh, cleaned up the sdmmc library (from the dark-samus a9lh fork)

loader/source/start.s

@@ -0,0 +1,15 @@
+.section .text.start
+.align 4
+.global _start
+_start:
+
+    @ Flush caches
+    mov r0, #0
+    mcr p15, 0, r0, c7, c5, 0  @ flush I-cache
+    mcr p15, 0, r0, c7, c6, 0  @ flush D-cache
+    mcr p15, 0, r0, c7, c10, 4 @ drain write buffer
+
+    bl main
+
+.die:
+    b .die