.gitignore: Do not ignore dsdl.asl file

dsdl.asl file is not autogenerated while all other dsdl_*.asl files are.
.hgignore is correct.

Signed-off-by: Frediano Ziglio <frediano.ziglio@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>

.gitignore

@@ -173,7 +173,7 @@ tools/firmware/extboot/extboot.img
 tools/firmware/extboot/signrom
 tools/firmware/hvmloader/acpi/mk_dsdt
 tools/firmware/hvmloader/acpi/dsdt*.c
-tools/firmware/hvmloader/acpi/dsdt*.asl
+tools/firmware/hvmloader/acpi/dsdt_*.asl
 tools/firmware/hvmloader/acpi/ssdt_*.h
 tools/firmware/hvmloader/hvmloader
 tools/firmware/hvmloader/roms.h