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
 

src/system/kernel/elf.cpp

@@ -2283,6 +2283,7 @@ load_kernel_add_on(const char *path)
 				// should check here for appropriate interpreter
 				continue;
 			case PT_PHDR:
+			case PT_STACK:
 				// we don't use it
 				continue;
 			default:

src/system/runtime_loader/elf_load_image.cpp

@@ -75,6 +75,7 @@ count_regions(const char* imagePath, char const* buff, int phnum, int phentsize)
 			case PT_PHDR:
 				// we don't use it
 				break;
+			case PT_EH_FRAME:
 			case PT_RELRO:
 				// not implemented yet, but can be ignored
 				break;
@@ -199,6 +200,7 @@ parse_program_headers(image_t* image, char* buff, int phnum, int phentsize)
 			case PT_PHDR:
 				// we don't use it
 				break;
+			case PT_EH_FRAME:
 			case PT_RELRO:
 				// not implemented yet, but can be ignored
 				break;