[gdb/testsuite] Add nopie in a few test-cases

When running test-case gdb.arch/i386-disp-step.exp with target board
unix/-m32/-fPIE/-pie we run into:
...
gdb compile failed, ld: i386-disp-step0.o: warning: relocation in read-only section `.text'
ld: warning: creating DT_TEXTREL in a PIE
...

Fix this by adding nopie in the compilation flags.

Likewise in a few other test-cases.

Tested on x86_64-linux.

gdb/testsuite/gdb.arch/i386-disp-step.exp

@@ -22,7 +22,11 @@ require is_x86_like_target
 
 standard_testfile .S
 
-if { [prepare_for_testing "failed to prepare" $testfile $srcfile] } {
+set opts {}
+lappend opts debug
+lappend opts nopie
+
+if { [prepare_for_testing "failed to prepare" $testfile $srcfile $opts] } {
     return -1
 }
 

gdb/testsuite/gdb.dwarf2/implptr.exp

@@ -26,6 +26,8 @@ standard_testfile .S
 set csrcfile ${testfile}.c
 set opts {}
 
+lappend opts nopie
+
 if [info exists COMPILE] {
     # make check RUNTESTFLAGS='gdb.dwarf2/implptr.exp COMPILE=1 CC_FOR_TARGET=gcc\ -m32'
     set srcfile ${csrcfile}

gdb/testsuite/gdb.dwarf2/pieces-optimized-out.exp

@@ -22,7 +22,11 @@ require dwarf2_support is_x86_like_target
 standard_testfile .S
 set csrcfile ${testfile}.c
 
-if {[prepare_for_testing "failed to prepare" ${testfile} $srcfile]} {
+set opts {}
+lappend opts debug
+lappend opts nopie
+
+if {[prepare_for_testing "failed to prepare" ${testfile} $srcfile $opts]} {
     return -1
 }
 

gdb/testsuite/gdb.dwarf2/typeddwarf.exp

@@ -29,7 +29,12 @@ if { [is_x86_like_target] } {
     return 0
 }
 
-if { [prepare_for_testing "failed to prepare" "${test}" ${sfile} {nodebug additional_flags=-nostdlib}] } {
+set opts {}
+lappend opts nodebug
+lappend opts additional_flags=-nostdlib
+lappend opts nopie
+
+if { [prepare_for_testing "failed to prepare" "${test}" ${sfile} $opts] } {
     return -1
 }