More progress on parsing elf files. Fixes to memfs file read/write

Increased inode block pointers to 40. The current maximum allowed (and checked).
Updates to file size after every file write ensures subsequent writes can
correctly operate using updated file size information (i.e. not try to add
more pages that are already present). We cannot do this inside write() because
directory writes rely on byte-granularity updates on file buffers, whereas
file updates are by page-granularity (currently).

tasks/test0/include/linker.lds

@@ -30,7 +30,14 @@ SECTIONS
 	/* rodata is needed else your strings will link at physical! */
 	.rodata : AT (ADDR(.rodata) - offset) { *(.rodata) }
 	.rodata1 : AT (ADDR(.rodata1) - offset) { *(.rodata1) }
-	.data : AT (ADDR(.data) - offset) { *(.data) }
+	.data : AT (ADDR(.data) - offset)
+	{
+		. = ALIGN(4K);
+		_start_test1 = .;
+		*(.test1)
+		_end_test1 = .;
+		*(.data)
+	}
 	.bss : AT (ADDR(.bss) - offset) { *(.bss) }
 	_end = .;
 }

tasks/test0/include/tests.h

@@ -10,6 +10,6 @@ int dirtest(void);
 int fileio(void);
 int fileio2(void);
 int clonetest(void);
-void exectest(void);
+int exectest(void);
 
 #endif /* __TEST0_TESTS_H__ */