PPC: simplify the bootloader linker script

the OF 2.0 COFF loader skips sections other than
.text .data and .bss, so merge others into those three.

src/system/ldscripts/ppc/boot_loader_openfirmware.ld

@@ -5,35 +5,35 @@ ENTRY(_start)
 
 SECTIONS
 {
-	. = 0x102000 + SIZEOF_HEADERS;
+	. = 0x202000 + SIZEOF_HEADERS;
 
 	__text_begin = .;
 
 	/* text/read-only data */
-	.text :	{ *(.text .text.* .gnu.linkonce.t.*) }
+	.text :	{ *(.text .text.* .gnu.linkonce.t.*)
-
+	          *(.rodata .rodata.* .gnu.linkonce.r.*)
-	.rodata : { *(.rodata .rodata.* .gnu.linkonce.r.*) }
+	          *(.sdata2) }
-	.sdata2 : { *(.sdata2) }
 
 	/* writable data  */
 	/* align to the same offset in the next page (for performance reasons
 	   (not that it really matters in the boot loader)) */
 	. = ALIGN(0x1000) + 0x1000 + (. & (0x1000 - 1));
 
+	.data : {
 		__ctor_list = .;
-	.ctors : { *(.ctors) }
+		*(.ctors)
 		__ctor_end = .;
 
 		__data_start = .;
-	.data : { *(.data .gnu.linkonce.d.*) }
+		*(.data .gnu.linkonce.d.*)
-	.data.rel.ro : { *(.data.rel.ro.local .data.rel.ro*) }
+		*(.data.rel.ro.local .data.rel.ro*)
-	.got : { *(.got .got2) }
+		*(.got .got2)
-	.sdata : { *(.sdata .sdata.* .gnu.linkonce.s.*) }
+		*(.sdata .sdata.* .gnu.linkonce.s.* .fixup) }
 
 	/* uninitialized data (in same segment as writable data) */
 	__bss_start = .;
-	.sbss : { *(.sbss .sbss.* .gnu.linkonce.sb.*) }
+	.bss : { *(.sbss .sbss.* .gnu.linkonce.sb.*)
-	.bss : {
+
 		*(.bss .bss.* .gnu.linkonce.b.*)
 		. = ALIGN(0x1000);
 	}
@@ -41,5 +41,5 @@ SECTIONS
 	_end = . ;
 
 	/* Strip unnecessary stuff */
-	/DISCARD/ : { *(.comment .note .eh_frame .dtors .debug_*) }
+	/DISCARD/ : { *(.comment .note .eh_frame .dtors .debug_* .gnu.attributes) }
 }