boot/ipl.h: remove aligned attribute from `struct ipl_parameter_block`
boot/ipl.h: remove aligned attribute from `struct ipl_parameter_block`

This fixes an error when genprotimg is compiled with clang and the
sanitizers address and undefined behaviour enabled.

pv/pv_ipib.c:47:33: runtime error: member access within misaligned address 0x62100000a100 for type 'IplParameterBlock' (aka 'struct ipl_parameter_block'), which requires 4096 byte alignment
0x62100000a100: note: pointer points here
 01 00 00 45  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  00 00 00 00
              ^
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior pv/pv_ipib.c:47:33 in

This change should be no problem as genprotimg is the only user.

Reviewed-by: Philipp Rudo <ebc9ed60c9e1dc6a17c00cf7f6009c740d3c3928@linux.ibm.com>
Signed-off-by: Marc Hartmayer <7bafc8cd4e6394916d396e4f8cde69753be8d066@linux.ibm.com>
Signed-off-by: Jan Höppner <96138615ab4af0813785fa10d283f3d37eca3b78@linux.ibm.com>

ibm-s390-tools/s390-tools,ibm-s390-tools/s390-tools,ibm-s390-tools/s390-tools,ibm-s390-tools/s390-tools