testsuite: Fix fallout of turning warnings into errors on 32-bit Arm

Since commits 2c3db94d ("c: Turn int-conversion warnings into
permerrors") and 55e94561 ("c: Turn -Wimplicit-function-declaration
into a permerror") these tests fail with errors such as:

  FAIL: gcc.target/arm/pr59858.c (test for excess errors)
  FAIL: gcc.target/arm/pr65647.c (test for excess errors)
  FAIL: gcc.target/arm/pr65710.c (test for excess errors)
  FAIL: gcc.target/arm/pr97969.c (test for excess errors)

Here's one example of the excess errors:

  FAIL: gcc.target/arm/pr65647.c (test for excess errors)
  Excess errors:
  /path/gcc.git/gcc/testsuite/gcc.target/arm/pr65647.c:6:17: error: initialization of 'int' from 'int *' makes integer from pointer without a cast [-Wint-conversion]
  /path/gcc.git/gcc/testsuite/gcc.target/arm/pr65647.c:6:51: error: initialization of 'int' from 'int *' makes integer from pointer without a cast [-Wint-conversion]
  /path/gcc.git/gcc/testsuite/gcc.target/arm/pr65647.c:6:62: error: initialization of 'int' from 'int *' makes integer from pointer without a cast [-Wint-conversion]
  /path/gcc.git/gcc/testsuite/gcc.target/arm/pr65647.c:7:48: error: initialization of 'int' from 'int *' makes integer from pointer without a cast [-Wint-conversion]
  /path/gcc.git/gcc/testsuite/gcc.target/arm/pr65647.c:8:9: error: initialization of 'int' from 'int *' makes integer from pointer without a cast [-Wint-conversion]
  /path/gcc.git/gcc/testsuite/gcc.target/arm/pr65647.c:24:5: error: initialization of 'int' from 'int *' makes integer from pointer without a cast [-Wint-conversion]
  /path/gcc.git/gcc/testsuite/gcc.target/arm/pr65647.c:25:5: error: initialization of 'int' from 'struct S1 *' makes integer from pointer without a cast [-Wint-conversion]
  /path/gcc.git/gcc/testsuite/gcc.target/arm/pr65647.c:41:3: error: implicit declaration of function 'fn3'; did you mean 'fn2'? [-Wimplicit-function-declaration]
  /path/gcc.git/gcc/testsuite/gcc.target/arm/pr65647.c:46:3: error: implicit declaration of function 'fn5'; did you mean 'fn4'? [-Wimplicit-function-declaration]
  /path/gcc.git/gcc/testsuite/gcc.target/arm/pr65647.c:57:16: error: implicit declaration of function 'fn6'; did you mean 'fn4'? [-Wimplicit-function-declaration]

PR rtl-optimization/59858 and PR target/65710 test the fix of an ICE.
PR target/65647 and PR target/97969 test for a compilation infinite loop.

Therefore, add -fpermissive so that the tests behave as they did previously.
Tested on armv8l-linux-gnueabihf.

gcc/testsuite/ChangeLog:
	* gcc.target/arm/pr59858.c: Add -fpermissive.
	* gcc.target/arm/pr65647.c: Likewise.
	* gcc.target/arm/pr65710.c: Likewise.
	* gcc.target/arm/pr97969.c: Likewise.