Add missing header.
Add missing header.

malloc/free are being used if SWIFTSHADER_TRANSLATOR_DISABLE_POOL_ALLOC
is defined.

Change-Id: I213c9d614b38fecdc673be5058d5f6f2bc579ca6
Reviewed-on: https://swiftshader-review.googlesource.com/19968
Reviewed-by: Nicolas Capens <51edc787c30f24c4904e8ffbb5523c3a9f7a451d@google.com>
Tested-by: Nicolas Capens <51edc787c30f24c4904e8ffbb5523c3a9f7a451d@google.com>

google/swiftshader,google/swiftshader,bkaradzic/SwiftShader,bkaradzic/SwiftShader,bkaradzic/SwiftShader,bkaradzic/SwiftShader,bkaradzic/SwiftShader,google/swiftshader