romcc: Increase base address in linux ld script

Newer versions of Linux implement a sysctl variable called vm.mmap_min_addr
that controls the minimum address a virtual memory mapping may have[1]. It is
usually set to 64KiB.

Map the start of the segment specified in util/romcc/tests/ldscript.ld to
128KiB, just to be sure.

[1]: https://www.kernel.org/doc/Documentation/sysctl/vm.txt

Change-Id: I72a5c65ca5e7d3a77d6ec897ae3287e3ea05cc2f
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Reviewed-on: https://review.coreboot.org/14277
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Martin Roth <martinroth@google.com>

util/romcc/tests/ldscript.ld

@@ -3,7 +3,7 @@ ENTRY(_start)
 
 SECTIONS
 {
-	. = 0x1000;
+	. = 0x20000;
 	__cpu_reset = 0xdeadbeef;
 	.text . : {
 		. = ALIGN(16);