ELF: Ignore PT_EH_FRAME and PT_STACK.

This allows Clang builds (linked with our cross binutils) to
at least start runtime_loader and then try to load launch_daemon.
That fails with an infinite loop somewhere...

headers/os/kernel/elf.h

@@ -322,6 +322,7 @@ typedef struct {
 #define PT_SHLIB		5
 #define PT_PHDR			6
 #define PT_TLS			7
+#define PT_EH_FRAME		0x6474e550
 #define PT_STACK		0x6474e551
 #define PT_RELRO		0x6474e552