Fix AIX build

[ayappanec]

AIX build with OpenXL broke after PR #4944 with the below errors.

In file included from ../kernel/power/sbgemv_t_vsx.c:31:
In file included from ../kernel/power/sbgemv_common.c:30:
../kernel/power/gemm_common.c:31:18: error: type specifier missing, defaults to 'int'; ISO C99 and later do not support implicit int [-Wimplicit-int]
31 | typedef __vector IFLOAT vec_bf16;
| ~~~~~~~~~~~~~~~~ ^
| int
../common.h:310:16: note: expanded from macro 'IFLOAT'
310 | #define IFLOAT bfloat16
| ^
In file included from ../kernel/power/sbgemv_t_vsx.c:31:
In file included from ../kernel/power/sbgemv_common.c:30:
../kernel/power/gemm_common.c:31:18: error: typedef redefinition with different types ('__vector int' (vector of 4 'int' values) vs 'uint16_t' (aka 'unsigned short'))
../common.h:310:16: note: expanded from macro 'IFLOAT'
310 | #define IFLOAT bfloat16
| ^
../common.h:265:18: note: previous definition is here
265 | typedef uint16_t bfloat16;
| ^
In file included from ../kernel/power/sbgemv_t_vsx.c:31:
In file included from ../kernel/power/sbgemv_common.c:30:
../kernel/power/gemm_common.c:31:24: error: expected ';' after top level declarator
31 | typedef __vector IFLOAT vec_bf16;
| ^
| ;
../kernel/power/gemm_common.c:72:13: error: unknown type name 'vec_bf16'
72 | FORCEINLINE vec_bf16 vec_loadN(void *src, BLASLONG n)
| ^

Looks like vector types will not work with typedef 'ed defines in AIX with OpenXL compiler.
Also bool type is used in the sbgemv_common_power10.c and needs the explicit include of stdbool.h in AIX.

[ChipKerchner]

There is also an issue with AIX gcc=10.3. Please hold off merging this until both compilers can be addressed.

[ayappanec]

I just addressed the build issues with gcc compiler also.

[ChipKerchner]

Looks good to me.

[ayappanec]

Thanks for the merge